Scene Manager: Load Publish and numbered instances

Load Publish (Loaded panel) searches every asset of the project, then
loads any of its published .blend files at any version, cast in the shot
or not. The file the casting would load and the latest version on this
site are preselected; a version not on this site is requested instead.
Built on the existing wtd_list_assets / wtd_get_asset_files /
wtd_get_revisions commands.

New instances are numbered (COL_bob_01, tree_01...), counting on from the
highest number in the file (SCENE_MANAGER_INSTANCE_NAME).

README: Pick Shot only lists shots that exist in Libreflow.

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

ui/panel.py

@@ -439,6 +439,7 @@ class _SceneLoadedPanel:
 
     def draw(self, context) -> None:
         layout = self.layout
+        layout.operator(sm.WTD_OT_scene_browse.bl_idname, text="Load Publish...", icon="VIEWZOOM")
         libraries = sm_library.managed_libraries()
         if not libraries:
             layout.label(text="Nothing loaded by the Scene Manager", icon="INFO")