Scene Manager: LOD switching; Shot Viewer renamed Shot Manager

LODs are child collections of the asset collection (COL_{asset}_LOD{n}).
Overrides hide the other LOD collections (viewport and render), keeping
the rig, pose and animation; collection instances instance the LOD
collection. Each instance has its own LOD, set per instance or for the
selection in the Loaded panel, kept through save, reload and updates.
Loading shows SCENE_MANAGER_DEFAULT_LOD (0).

The Shot Viewer panel is now "Shot Manager" and starts closed. Code
names and SHOT_VIEWER_* config keys are unchanged.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

__init__.py

@@ -46,7 +46,7 @@ def register() -> None:
     # Register the rename tool (settings and operator, before its panel)
     rename.register()
 
-    # Register the shot viewer (settings and operators, before its panel)
+    # Register the shot manager (settings and operators, before its panel)
     shot_viewer.register()
 
     # Register the scene manager (settings and operators, before its panels)
@@ -80,7 +80,7 @@ def unregister() -> None:
     # Unregister the rename tool (after its panel)
     rename.unregister()
 
-    # Unregister the shot viewer (after its panel)
+    # Unregister the shot manager (after its panel)
     shot_viewer.unregister()
 
     # Unregister the scene manager (after its panels)