Add tags to all entity types with chip-based input and autocomplete

- Add `tags: List[str]` field to all 13 entity types (devices, output targets,
  CSS sources, picture sources, audio sources, value sources, sync clocks,
  automations, scene presets, capture/audio/PP/pattern templates)
- Update all stores, schemas, and route handlers for tag CRUD
- Add GET /api/v1/tags endpoint aggregating unique tags across all stores
- Create TagInput component with chip display, autocomplete dropdown,
  keyboard navigation, and API-backed suggestions
- Display tag chips on all entity cards (searchable via existing text filter)
- Add tag input to all 14 editor modals with dirty check support
- Add CSS styles and i18n keys (en/ru/zh) for tag UI
- Also includes code review fixes: thread safety, perf, store dedup

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

server/src/wled_controller/storage/output_target.py

@@ -1,8 +1,8 @@
 """Output target base data model."""
 
-from dataclasses import dataclass
+from dataclasses import dataclass, field
 from datetime import datetime
-from typing import Optional
+from typing import List, Optional
 
 
 @dataclass
@@ -15,6 +15,7 @@ class OutputTarget:
     created_at: datetime
     updated_at: datetime
     description: Optional[str] = None
+    tags: List[str] = field(default_factory=list)
 
     def register_with_manager(self, manager) -> None:
         """Register this target with the processor manager. Subclasses override."""
@@ -26,12 +27,15 @@ class OutputTarget:
 
     def update_fields(self, *, name=None, device_id=None, picture_source_id=None,
                       settings=None, key_colors_settings=None, description=None,
+                      tags: Optional[List[str]] = None,
                       **_kwargs) -> None:
         """Apply mutable field updates. Base handles common fields; subclasses handle type-specific ones."""
         if name is not None:
             self.name = name
         if description is not None:
             self.description = description
+        if tags is not None:
+            self.tags = tags
 
     @property
     def has_picture_source(self) -> bool:
@@ -45,6 +49,7 @@ class OutputTarget:
             "name": self.name,
             "target_type": self.target_type,
             "description": self.description,
+            "tags": self.tags,
             "created_at": self.created_at.isoformat(),
             "updated_at": self.updated_at.isoformat(),
         }