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/routes/base_model_routes.py

@@ -24,9 +24,11 @@ from ..services.use_cases import (
     AutoOrganizeUseCase,
     BulkMetadataRefreshUseCase,
     DownloadModelUseCase,
+    FilenameTemplateUseCase,
 )
 from ..services.websocket_progress_callback import (
     WebSocketBroadcastCallback,
+    WebSocketFilenameTemplateProgressCallback,
     WebSocketProgressCallback,
 )
 from ..utils.exif_utils import ExifUtils
@@ -37,6 +39,7 @@ from .handlers.model_handlers import (
     ModelAutoOrganizeHandler,
     ModelCivitaiHandler,
     ModelDownloadHandler,
+    ModelFilenameTemplateHandler,
     ModelHandlerSet,
     ModelListingHandler,
     ModelManagementHandler,
@@ -83,6 +86,9 @@ class BaseModelRoutes(ABC):
         self.model_lifecycle_service: ModelLifecycleService | None = None
         self.websocket_progress_callback = WebSocketProgressCallback()
         self.metadata_progress_callback = WebSocketBroadcastCallback()
+        self.filename_template_progress_callback = (
+            WebSocketFilenameTemplateProgressCallback()
+        )
 
         self._handler_set: ModelHandlerSet | None = None
         self._handler_mapping: Dict[str, Callable[[web.Request], Awaitable[web.Response]]] | None = None
@@ -202,6 +208,17 @@ class BaseModelRoutes(ABC):
             ws_manager=self._ws_manager,
             logger=logger,
         )
+        filename_template_use_case = FilenameTemplateUseCase(
+            scanner=service.scanner,
+            lifecycle_service=self._ensure_lifecycle_service(),
+            lock_provider=self._ws_manager,
+            model_type=service.model_type,
+        )
+        filename_template = ModelFilenameTemplateHandler(
+            use_case=filename_template_use_case,
+            progress_callback=self.filename_template_progress_callback,
+            logger=logger,
+        )
         updates = ModelUpdateHandler(
             service=service,
             update_service=update_service,
@@ -218,6 +235,7 @@ class BaseModelRoutes(ABC):
             civitai=civitai,
             move=move,
             auto_organize=auto_organize,
+            filename_template=filename_template,
             updates=updates,
         )