feat(settings): filename templates for download and bulk rename (#1071)

Add per-model-type filename templates ({model_name}, {version_name},
{base_model}, {author}, {first_tag}, {hash_short}, {original_name}) so
downloaded files get informative names instead of e.g. V1.safetensors.
Empty template keeps the current filename (opt-in, off by default).

- apply template automatically after downloads; rename conflicts keep
  the original name and never fail the download
- record original_file_name in metadata on rename for traceability
- bulk apply via GET|POST /api/lm/{prefix}/apply-filename-template with
  WebSocket progress, sharing the auto-organize lock
- settings UI lives in the new Organization tab with validation, live
  preview, and per-type 'apply to library' actions

py/services/websocket_manager.py

@@ -20,6 +20,8 @@ class WebSocketManager:
         self._last_init_progress: Dict[str, Dict[str, Any]] = {}
         # Add auto-organize progress tracking
         self._auto_organize_progress: Optional[Dict[str, Any]] = None
+        # Add filename template progress tracking
+        self._filename_template_progress: Optional[Dict[str, Any]] = None
         # Add recipe rematch progress tracking
         self._recipe_rematch_progress: Optional[Dict[str, Any]] = None
         self._auto_organize_lock = asyncio.Lock()
@@ -205,6 +207,26 @@ class WebSocketManager:
     def cleanup_auto_organize_progress(self):
         """Clear auto-organize progress data"""
         self._auto_organize_progress = None
+
+    async def broadcast_filename_template_progress(self, data: Dict[str, Any]):
+        """Broadcast filename template progress to connected clients"""
+        self._filename_template_progress = data
+        await self.broadcast(data)
+
+    def get_filename_template_progress(self) -> Optional[Dict[str, Any]]:
+        """Get current filename template progress"""
+        return self._filename_template_progress
+
+    def cleanup_filename_template_progress(self):
+        """Clear filename template progress data"""
+        self._filename_template_progress = None
+
+    def is_filename_template_running(self) -> bool:
+        """Check if a filename template operation is currently running"""
+        if not self._filename_template_progress:
+            return False
+        status = self._filename_template_progress.get('status')
+        return status in ['started', 'processing']
     
     async def broadcast_recipe_rematch_progress(self, data: Dict[str, Any]):
         """Broadcast recipe rematch progress to connected clients"""