refactor(gui): streamline SHA display logic in UpdateDialog

- Remove the _available_sha_display method and directly utilize _short_sha for clarity.
- Update new version label to reflect the installed SHA when no pending SHA is available.
- Clean up related unit tests to align with the updated display logic.

.git_archival.txt

@@ -1 +1 @@
-node: $Format:%H$
+node: 0a2b8c77b887a097113859aba3eeec0decd006b7

gui/main.py

@@ -533,10 +533,6 @@ class UpdateDialog(QDialog):
             return "Unknown"
         return sha[:8]
 
-    @classmethod
-    def _available_sha_display(cls, sha: str | None) -> str:
-        return cls._short_sha(sha) if sha else "Current"
-
     @classmethod
     def _installed_sha_display(cls) -> str:
         return cls._short_sha(UpdateThread.read_installed_sha())
@@ -592,7 +588,7 @@ class UpdateDialog(QDialog):
         self.cancel_btn.setText("Close")
 
         tool_sha = self._pending_tool_sha
-        self.new_version_label.setText(self._available_sha_display(tool_sha))
+        self.new_version_label.setText(self._short_sha(tool_sha))
 
         if not tool_sha:
             self.headline_label.setText("You're up to date")
@@ -646,7 +642,7 @@ class UpdateDialog(QDialog):
                 f"No newer build found on {UpdateThread.REPO_BRANCH}."
             )
             self.subtitle_label.setText("You're running the latest version.")
-            self.new_version_label.setText("Current")
+            self.new_version_label.setText(self._installed_sha_display())
         elif message.startswith("updated:"):
             sha = message.split(":", 1)[1]
             self._pending_tool_sha = None

tests/test_bundled_updates.py

@@ -300,21 +300,6 @@ class CheckToolUpdateTests(unittest.TestCase):
             self.assertIsNone(check_tool_update())
 
 
-class UpdateDialogDisplayTests(unittest.TestCase):
-    def test_available_version_says_current_when_up_to_date(self):
-        from gui.main import UpdateDialog
-
-        self.assertEqual(UpdateDialog._available_sha_display(None), "Current")
-
-    def test_available_version_shows_pending_sha(self):
-        from gui.main import UpdateDialog
-
-        self.assertEqual(
-            UpdateDialog._available_sha_display("1234567890abcdef"),
-            "12345678",
-        )
-
-
 class AceBundledOnlyTests(unittest.TestCase):
     def _ace_paths(self, base: Path) -> dict:
         offline = base / "offline"