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>

config.py

@@ -234,7 +234,7 @@ RENAME_TYPE_SUFFIXES = {
 }
 
 # --------------------------------------------------------------------------- #
-# Shot viewer
+# Shot manager
 # --------------------------------------------------------------------------- #
 # Groups of the rig quick selection: an armature goes to the first group whose
 # pattern matches its name, one of its collections or its library file name.
@@ -253,11 +253,11 @@ SHOT_VIEWER_ASSET_TYPE_GROUPS = {
     "vehicles": "Props",
 }
 
-# Shots added by the shot viewer. TODO: confirm with production.
+# Shots added by the shot manager. TODO: confirm with production.
 SHOT_NAME_FORMAT = "sh{:04d}"
-# Sequence of the scene (number set in the Shot Viewer panel): SEQUENCE_NAME_FORMAT.format(number).
+# Sequence of the scene (number set in the Shot Manager panel): SEQUENCE_NAME_FORMAT.format(number).
 SEQUENCE_NAME_FORMAT = "sq{:04d}"
-# Cameras added by the shot viewer. Tokens: {prefix} (OBJECT_PREFIXES["CAMERA"]),
+# Cameras added by the shot manager. Tokens: {prefix} (OBJECT_PREFIXES["CAMERA"]),
 # {sequence} (SEQUENCE_NAME_FORMAT) and {shot} (the shot name).
 SHOT_CAMERA_NAME_FORMAT = "{prefix}{sequence}_{shot}"
 # Their rig, same tokens with {prefix} = OBJECT_PREFIXES["ARMATURE"].
@@ -298,6 +298,12 @@ SCENE_MANAGER_LINK_MODES = {
     "vehicles": "OVERRIDE",
     "*": "INSTANCE",
 }
+# Levels of detail: child collections of the asset collection, one per LOD ({asset} =
+# asset name, {lod} = LOD number). An override shows one and hides the others; a
+# collection instance instances it.
+SCENE_MANAGER_LOD_COLLECTION = "COL_{asset}_LOD{lod}"
+# LOD shown when an asset is loaded (the lowest one when missing). None: as in the file.
+SCENE_MANAGER_DEFAULT_LOD = 0
 # Collection gathering the loaded assets of a type, under the scene collection.
 SCENE_MANAGER_TYPE_COLLECTION = "COL_{asset_type}"
 # Default task of the assetize dialog.