feat(saga): enhance hover functionality and ownership management

- Introduce new hover command for second unit in saga scrubbing
- Implement logic to manage hover ownership and prevent visual conflicts
- Update WatchCaption to track blocked dossier writes during hover
- Refactor LifeSagaViewController to maintain hover session integrity
- Enhance harness scenarios to validate new hover behaviors and ownership checks

IdleSpectator/AgentHarness.cs

@@ -4280,6 +4280,99 @@ public static class AgentHarness
                 break;
             }
 
+            case "saga_scrub_hover_second":
+            {
+                LifeSagaRail.Refresh();
+                if (!LifeSagaViewController.IsHoverPreview)
+                {
+                    LifeSagaRail.ShowHover(0);
+                    WatchCaption.RequestRelayout();
+                }
+
+                long firstId = LifeSagaViewController.HoverPreviewId;
+                string firstName = WatchCaption.VisibleNametagText;
+                int secondIndex = -1;
+                for (int i = 0; i < LifeSagaRoster.Cap; i++)
+                {
+                    long id = LifeSagaRail.UnitIdAt(i);
+                    if (id != 0 && id != firstId)
+                    {
+                        secondIndex = i;
+                        break;
+                    }
+                }
+
+                LifeSagaRail.HideHover();
+                bool deferredHeld = LifeSagaViewController.IsHoverPreview
+                                    && LifeSagaViewController.HoverPreviewId == firstId
+                                    && InterestDirector.ReadPauseActive
+                                    && string.Equals(
+                                        WatchCaption.VisibleNametagText,
+                                        firstName,
+                                        StringComparison.Ordinal);
+
+                if (secondIndex >= 0)
+                {
+                    LifeSagaRail.ShowHover(secondIndex);
+                    WatchCaption.RequestRelayout();
+                }
+
+                LifeSagaViewModel model = LifeSagaViewController.BuildEffectivePresentation();
+                string expected = (model?.Name ?? "").Replace("★ ", "").Trim();
+                string beforeWriter = WatchCaption.VisibleNametagText;
+                int beforeFont = WatchCaption.VisibleNametagFontSize;
+                Vector2 beforeAvatar = DossierAvatar.HostAnchoredPosition;
+                int blockedBefore = WatchCaption.SagaHoverBlockedDossierWrites;
+
+                // Reproduce the real contention: the camera dossier receives a normal bind
+                // while a different Saga glyph owns the shared header.
+                Actor focus = MoveCamera.hasFocusUnit() ? MoveCamera._focus_unit : null;
+                if (focus != null && focus.isAlive())
+                {
+                    WatchCaption.SetFromActor(focus);
+                }
+                WatchCaption.Update();
+                WatchCaption.RequestRelayout();
+
+                string afterWriter = WatchCaption.VisibleNametagText;
+                int afterFont = WatchCaption.VisibleNametagFontSize;
+                Vector2 afterAvatar = DossierAvatar.HostAnchoredPosition;
+                long secondId = LifeSagaViewController.HoverPreviewId;
+                bool correctSecond = secondIndex >= 0
+                                     && secondId != 0
+                                     && secondId != firstId
+                                     && !string.IsNullOrEmpty(expected)
+                                     && afterWriter.IndexOf(expected, StringComparison.Ordinal) >= 0;
+                bool stable = string.Equals(beforeWriter, afterWriter, StringComparison.Ordinal)
+                              && beforeFont == afterFont
+                              && Vector2.Distance(beforeAvatar, afterAvatar) < 0.1f;
+                bool blocked = WatchCaption.SagaHoverBlockedDossierWrites > blockedBefore;
+                bool ok = deferredHeld
+                          && correctSecond
+                          && stable
+                          && blocked
+                          && InterestDirector.ReadPauseActive;
+                if (ok)
+                {
+                    _cmdOk++;
+                }
+                else
+                {
+                    _cmdFail++;
+                }
+
+                Emit(
+                    cmd,
+                    ok,
+                    detail:
+                    $"first={firstId} second={secondId} index={secondIndex} held={deferredHeld} "
+                    + $"name='{firstName}'/'{beforeWriter}'/'{afterWriter}' expected='{expected}' "
+                    + $"font={beforeFont}/{afterFont} avatar={beforeAvatar}/{afterAvatar} "
+                    + $"blocked={blockedBefore}/{WatchCaption.SagaHoverBlockedDossierWrites} "
+                    + $"pause={InterestDirector.ReadPauseActive}");
+                break;
+            }
+
             case "saga_hide_hover":
             {
                 LifeSagaRail.HideHover();
@@ -10403,6 +10496,11 @@ public static class AgentHarness
                     + $"visible={DossierAvatar.HostVisible} pass={pass}";
                 break;
             }
+            case "saga_hover_nametag_ownership":
+            {
+                pass = WatchCaption.HarnessProbeSagaHoverNametagOwnership(out detail);
+                break;
+            }
             case "caption_mc_identity":
             {
                 string idLine = WatchCaption.LastHeadline ?? "";

IdleSpectator/HarnessScenarios.cs

@@ -3978,6 +3978,7 @@ internal static class HarnessScenarios
             Step("sad8b", "pick_unit", asset: "human", value: "other"),
             Step("sad9", "focus", asset: "human"),
             Step("sad10", "saga_force_admit_focus"),
+            Step("sad10p", "saga_force_admit_partner"),
             Step("sad10a", "saga_memory_record_focus", asset: "War", value: "opposing commander",
                 expect: "harness_cast_relation"),
             Step("sad11", "assert", expect: "saga_tab_selected", value: "dossier"),
@@ -4010,6 +4011,8 @@ internal static class HarnessScenarios
             Step("sad19", "assert", expect: "saga_tab_effective", value: "saga"),
             Step("sad20", "assert", expect: "saga_hover_preview", value: "true"),
             Step("sad21", "assert", expect: "saga_read_pause", value: "true"),
+            Step("sad21a", "saga_scrub_hover_second"),
+            Step("sad21a2", "assert", expect: "saga_hover_nametag_ownership"),
             Step("sad21b", "saga_hide_hover"),
             Step("sad21d", "saga_hover_tick_away"),
             Step("sad21h", "assert", expect: "saga_hover_preview", value: "false"),

IdleSpectator/Story/LifeSagaViewController.cs

@@ -122,7 +122,10 @@ public static class LifeSagaViewController
             return;
         }
 
-        FinishHoverExit();
+        // PointerExit is delivered before PointerEnter when scrubbing directly from one
+        // glyph to another. Keep Saga ownership alive across that event handoff so the
+        // dossier cannot paint one intermediate header frame.
+        _hoverExitAt = Time.unscaledTime + HoverExitGraceSeconds;
     }
 
     public static void Tick()
@@ -155,8 +158,14 @@ public static class LifeSagaViewController
 
     public static void CancelPreviewAndPause()
     {
+        bool hadPreview = _hoverPreviewId != 0;
         _hoverExitAt = -1f;
         _hoverPreviewId = 0;
+        if (hadPreview)
+        {
+            WatchCaption.EndSagaHoverSession();
+        }
+
         if (_pauseHeld)
         {
             InterestDirector.ReleaseReadPause(ReadPauseOwner);
@@ -192,6 +201,7 @@ public static class LifeSagaViewController
     {
         _hoverExitAt = -1f;
         _hoverPreviewId = 0;
+        WatchCaption.EndSagaHoverSession();
         if (_pauseHeld)
         {
             InterestDirector.ReleaseReadPause(ReadPauseOwner);

IdleSpectator/WatchCaption.cs

@@ -131,6 +131,7 @@ public static class WatchCaption
     // LastHeadline. Keep its display text and entry typography separate from that cache.
     private static string _sagaHoverHeadline = "";
     private static int _sagaHoverFontCeiling;
+    private static int _sagaHoverBlockedDossierWrites;
     // OwnedEventReason performs stranger-name presentability checks against the living
     // population. A developed world makes that expensive, while the active director
     // candidate is normally unchanged for many 0.2-second caption refreshes.
@@ -181,6 +182,7 @@ public static class WatchCaption
     public static string VisibleNametagText => _nameText != null ? (_nameText.text ?? "") : "";
     public static int VisibleNametagFontSize => _nameText != null ? _nameText.fontSize : 0;
     public static int SagaHoverFontCeiling => _sagaHoverFontCeiling;
+    public static int SagaHoverBlockedDossierWrites => _sagaHoverBlockedDossierWrites;
 
     public static string LastDetail { get; private set; } = "";
 
@@ -572,7 +574,7 @@ public static class WatchCaption
 
         if (_nameText != null && (string.IsNullOrEmpty(_nameText.text) || _current == null))
         {
-            _nameText.text = "Idle Spectator";
+            PaintDossierHeadline("Idle Spectator");
             LastHeadline = "Idle Spectator";
         }
 
@@ -661,10 +663,7 @@ public static class WatchCaption
         _boundActor = null;
         EnsureBuilt();
         ApplyVisual(null, null);
-        if (_nameText != null)
-        {
-            _nameText.text = LastHeadline;
-        }
+        PaintDossierHeadline(LastHeadline);
 
         Relayout(false, 0, 0, false, false, 0);
         SetVisible(ModSettings.ShowDossierCaption && SpectatorMode.Active);
@@ -804,9 +803,9 @@ public static class WatchCaption
             {
                 ApplyVisual(focus ?? _boundActor, _current);
             }
-            else if (_nameText != null)
+            else
             {
-                _nameText.text = LastHeadline;
+                PaintDossierHeadline(LastHeadline);
                 Relayout(false, 0, 0, false, false, 0);
             }
 
@@ -815,10 +814,13 @@ public static class WatchCaption
 
         // Safety net: any focus change that skipped SetFromActor (or rematched follow)
         // must not leave the nametag on the previous person for a frame.
-        // Caption Identity/Beat/Context always track camera focus; hover only adds panel depth.
+        // Camera dossier state tracks focus, but Saga hover exclusively owns painted chrome.
         long perfStarted = StartPerfSample();
         LifeSagaViewController.Tick();
+        if (!LifeSagaViewController.IsHoverPreview)
+        {
             ReconcileDossierToFocus();
+        }
         LastReconcileMs = EndPerfSample(perfStarted);
         float now = Time.unscaledTime;
         if (now < _nextRoutineLiveRefreshAt)
@@ -959,11 +961,26 @@ public static class WatchCaption
     public static void BeginSagaHoverSession()
     {
         _sagaHoverHeadline = "";
+        _sagaHoverBlockedDossierWrites = 0;
         _sagaHoverFontCeiling = _nameText != null
             ? Mathf.Clamp(_nameText.fontSize, 7, 10)
             : 10;
     }
 
+    /// <summary>Return nametag ownership to the camera dossier after a true rail exit.</summary>
+    public static void EndSagaHoverSession()
+    {
+        _sagaHoverHeadline = "";
+        _sagaHoverFontCeiling = 0;
+        string shown = LastHeadline ?? "";
+        if (shown.Length > 48)
+        {
+            shown = CaptionComposer.TruncateIdentity(shown, 48);
+        }
+
+        PaintDossierHeadline(shown);
+    }
+
     /// <summary>
     /// Swap the hovered identity before building Cast/Legacy. This keeps pointer feedback
     /// immediate even when the deeper saga model has several relationships to resolve.
@@ -995,6 +1012,47 @@ public static class WatchCaption
         ApplySagaHoverHeader(model, deferPortraitReveal: true);
     }
 
+    /// <summary>Harness: prove a camera-dossier write cannot replace a hovered identity.</summary>
+    public static bool HarnessProbeSagaHoverNametagOwnership(out string detail)
+    {
+        string before = VisibleNametagText;
+        int blockedBefore = _sagaHoverBlockedDossierWrites;
+        PaintDossierHeadline("__dossier_writer_probe__");
+        string after = VisibleNametagText;
+        bool pass = LifeSagaViewController.IsHoverPreview
+                    && !string.IsNullOrEmpty(before)
+                    && string.Equals(before, after, StringComparison.Ordinal)
+                    && _sagaHoverBlockedDossierWrites == blockedBefore + 1;
+        detail =
+            $"hover={LifeSagaViewController.HoverPreviewId} before='{before}' after='{after}' "
+            + $"blocked={blockedBefore}/{_sagaHoverBlockedDossierWrites} pass={pass}";
+        return pass;
+    }
+
+    /// <summary>
+    /// Single camera-dossier nametag write gate. Saga hover is the exclusive visual
+    /// owner even while camera callbacks continue updating the underlying dossier model.
+    /// </summary>
+    private static void PaintDossierHeadline(string text)
+    {
+        if (_nameText == null)
+        {
+            return;
+        }
+
+        if (LifeSagaViewController.IsHoverPreview)
+        {
+            _sagaHoverBlockedDossierWrites++;
+            return;
+        }
+
+        string next = text ?? "";
+        if (!string.Equals(_nameText.text, next, StringComparison.Ordinal))
+        {
+            _nameText.text = next;
+        }
+    }
+
     /// <summary>
     /// A same-subject camera event can change its orange reason without rebuilding the
     /// dossier. Refresh only the owned reason/spine so UI and camera telemetry commit together.
@@ -1401,20 +1459,14 @@ public static class WatchCaption
                         shown = CaptionComposer.TruncateIdentity(shown, 48);
                     }
 
-                    if (!string.Equals(_nameText.text, shown, StringComparison.Ordinal))
-                    {
-                        _nameText.text = shown;
-                    }
+                    PaintDossierHeadline(shown);
                 }
             }
             else if (_current != null && !string.IsNullOrEmpty(_current.Headline))
             {
                 // Fallen/archive: Compose has no live focus - keep dossier headline.
                 LastHeadline = _current.Headline;
-                if (_nameText != null)
-                {
-                    _nameText.text = LastHeadline;
-                }
+                PaintDossierHeadline(LastHeadline);
             }
         }
 
@@ -1674,6 +1726,13 @@ public static class WatchCaption
             return;
         }
 
+        // A delayed model from the previous glyph must never repaint a newer hover.
+        if (!LifeSagaViewController.IsHoverPreview
+            || model.UnitId != LifeSagaViewController.HoverPreviewId)
+        {
+            return;
+        }
+
         Actor actor = EventFeedUtil.FindAliveById(model.UnitId);
         string name = (model.Name ?? "").Trim();
         if (name.StartsWith("★ ", StringComparison.Ordinal))
@@ -1905,7 +1964,10 @@ public static class WatchCaption
     /// <summary>Keep nametag Identity in sync via CaptionComposer (MC title or species/job).</summary>
     private static void RefreshLiveIdentity()
     {
-        if (!_visible || _current == null || _headlineLocked)
+        if (!_visible
+            || _current == null
+            || _headlineLocked
+            || LifeSagaViewController.IsHoverPreview)
         {
             return;
         }
@@ -2282,6 +2344,15 @@ public static class WatchCaption
                        && actor.getID() == dossier.UnitId;
         _boundActor = hasLive ? actor : null;
 
+        // Saga hover owns the complete header/body presentation. SetFromActor and other
+        // camera callbacks may still update the dossier snapshot, but they cannot repaint
+        // shared UI until the hover session ends.
+        if (LifeSagaViewController.IsHoverPreview)
+        {
+            _sagaHoverBlockedDossierWrites++;
+            return;
+        }
+
         if (_speciesIcon != null)
         {
             Sprite species = null;
@@ -2318,12 +2389,10 @@ public static class WatchCaption
             _sexIcon.gameObject.SetActive(hasSex);
         }
 
-        if (_nameText != null)
-        {
-            _nameText.text = dossier != null && !string.IsNullOrEmpty(dossier.Headline)
+        PaintDossierHeadline(
+            dossier != null && !string.IsNullOrEmpty(dossier.Headline)
                 ? dossier.Headline
-                : "";
-        }
+                : "");
 
         bool hasBody = dossier != null && dossier.UnitId != 0;
         bool hoverDepth = LifeSagaViewController.IsHoverPreview;

docs/five-mc-ensemble-plan.md

@@ -201,6 +201,8 @@ Recognition should come from repeated, stable signals rather than extra prose on
 - Identity remains `Name · real title`, otherwise `Name (species/job)`.
 - Hover remains the place for Cast and Legacy depth; the live caption stays Identity + Beat +
   Context.
+- Treat a glyph-to-glyph scrub as one hover ownership session: defer exit briefly, block all
+  camera-dossier writes to shared header chrome, and restore the camera name only after a true exit.
 
 ### MC connection in the camera dossier
 

docs/life-saga.md

@@ -219,6 +219,10 @@ Quiet can refresh briefly when a soft crumb ends (bounded).
   not call the population-counting dossier builder.
 - Hover fitting reads its own display headline rather than the camera dossier's cached identity;
   repeated relayouts therefore cannot briefly restore the wrong name or enlarge the font.
+- Saga owns the shared nametag/species/sex/portrait chrome exclusively for the whole hover session.
+  Camera dossier callbacks may update their semantic snapshot but cannot repaint that chrome.
+- Glyph exit is deferred for 50 ms; entering another glyph cancels the exit, producing an atomic
+  cross-glyph handoff with no intermediate dossier name or typography frame.
 - Rail face animation refreshes the Active glyph ~1/s; other glyphs stay static between structure changes.
 - Missing live rail frames retry at most one inactive slot per ~1s rail tick; successful captures
   replace the temporary species icon and unsuccessful attempts never discard an older live frame.