feat(download): add Hugging Face model download to standalone UI wizard (#965, #977)

Integrate HF model downloading into the existing CivitAI-style wizard flow:
- URL type detection (civitai / hf-resolve / hf-repo / direct-http)
- Repo file explorer with checkbox-based file selection
- Batch/queue download with per-file WebSocket progress
- Aria2 backend support (respects download_backend setting)
- Scanner cache integration via create_default_metadata + add_model_to_cache
- i18n updates for all 10 locales

py/routes/misc_route_registrar.py

@@ -94,6 +94,13 @@ MISC_ROUTE_DEFINITIONS: tuple[RouteDefinition, ...] = (
     RouteDefinition(
         "GET", "/api/lm/delete-model-version", "delete_model_version"
     ),
+    # Hugging Face model endpoints
+    RouteDefinition(
+        "GET", "/api/lm/hf-repo-files", "get_hf_repo_files"
+    ),
+    RouteDefinition(
+        "POST", "/api/lm/download-hf-model", "download_hf_model"
+    ),
 )