feat: asset-based image/video sources, notification sounds, UI improvements

- Replace URL-based image_source/url fields with image_asset_id/video_asset_id
  on StaticImagePictureSource and VideoCaptureSource (clean break, no migration)
- Resolve asset IDs to file paths at runtime via AssetStore.get_file_path()
- Add EntitySelect asset pickers for image/video in stream editor modal
- Add notification sound configuration (global sound + per-app overrides)
- Unify per-app color and sound overrides into single "Per-App Overrides" section
- Persist notification history between server restarts
- Add asset management system (upload, edit, delete, soft-delete)
- Replace emoji buttons with SVG icons throughout UI
- Various backend improvements: SQLite stores, auth, backup, MQTT, webhooks

server/src/wled_controller/api/routes/system.py

@@ -130,17 +130,19 @@ async def get_version():
 async def list_all_tags(_: AuthRequired):
     """Get all tags used across all entities."""
     all_tags: set[str] = set()
+    from wled_controller.api.dependencies import get_asset_store
     store_getters = [
         get_device_store, get_output_target_store, get_color_strip_store,
         get_picture_source_store, get_audio_source_store, get_value_source_store,
         get_sync_clock_store, get_automation_store, get_scene_preset_store,
         get_template_store, get_audio_template_store, get_pp_template_store,
-        get_pattern_template_store,
+        get_pattern_template_store, get_asset_store,
     ]
     for getter in store_getters:
         try:
             store = getter()
-        except RuntimeError:
+        except RuntimeError as e:
+            logger.debug("Store not available during entity count: %s", e)
             continue
         # BaseJsonStore subclasses provide get_all(); DeviceStore provides get_all_devices()
         fn = getattr(store, "get_all", None) or getattr(store, "get_all_devices", None)
@@ -211,10 +213,10 @@ async def get_displays(
     except ValueError as e:
         raise HTTPException(status_code=400, detail=str(e))
     except Exception as e:
-        logger.error(f"Failed to get displays: {e}")
+        logger.error("Failed to get displays: %s", e, exc_info=True)
         raise HTTPException(
             status_code=500,
-            detail=f"Failed to retrieve display information: {str(e)}"
+            detail="Internal server error"
         )
 
 
@@ -232,10 +234,10 @@ async def get_running_processes(_: AuthRequired):
         sorted_procs = sorted(processes)
         return ProcessListResponse(processes=sorted_procs, count=len(sorted_procs))
     except Exception as e:
-        logger.error(f"Failed to get processes: {e}")
+        logger.error("Failed to get processes: %s", e, exc_info=True)
         raise HTTPException(
             status_code=500,
-            detail=f"Failed to retrieve process list: {str(e)}"
+            detail="Internal server error"
         )
 
 
@@ -300,7 +302,7 @@ def list_api_keys(_: AuthRequired):
     """List API key labels (read-only; keys are defined in the YAML config file)."""
     config = get_config()
     keys = [
-        {"label": label, "masked": key[:4] + "****" + key[-4:] if len(key) >= 8 else "****"}
+        {"label": label, "masked": key[:4] + "****" if len(key) >= 8 else "****"}
         for label, key in config.auth.api_keys.items()
     ]
     return {"keys": keys, "count": len(keys)}