Add CSPT entity, processed CSS source type, reverse filter, and UI improvements

- Add Color Strip Processing Template (CSPT) entity: reusable filter chains
  for 1D LED strip postprocessing (backend, storage, API, frontend CRUD)
- Add "processed" color strip source type that wraps another CSS source and
  applies a CSPT filter chain (dataclass, stream, schema, modal, cards)
- Add Reverse filter for strip LED order reversal
- Add CSPT and processed CSS nodes/edges to visual graph editor
- Add CSPT test preview WS endpoint with input source selection
- Add device settings CSPT template selector (add + edit modals with hints)
- Use icon grids for palette quantization preset selector in filter lists
- Use EntitySelect for template references and test modal source selectors
- Fix filters.css_filter_template.desc missing localization
- Fix icon grid cell height inequality (grid-auto-rows: 1fr)
- Rename "Processed" subtab to "Processing Templates"
- Localize all new strings (en/ru/zh)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

server/src/wled_controller/main.py

@@ -31,6 +31,7 @@ from wled_controller.storage.value_source_store import ValueSourceStore
 from wled_controller.storage.automation_store import AutomationStore
 from wled_controller.storage.scene_preset_store import ScenePresetStore
 from wled_controller.storage.sync_clock_store import SyncClockStore
+from wled_controller.storage.color_strip_processing_template_store import ColorStripProcessingTemplateStore
 from wled_controller.core.processing.sync_clock_manager import SyncClockManager
 from wled_controller.core.automations.automation_engine import AutomationEngine
 from wled_controller.core.mqtt.mqtt_service import MQTTService
@@ -61,6 +62,7 @@ value_source_store = ValueSourceStore(config.storage.value_sources_file)
 automation_store = AutomationStore(config.storage.automations_file)
 scene_preset_store = ScenePresetStore(config.storage.scene_presets_file)
 sync_clock_store = SyncClockStore(config.storage.sync_clocks_file)
+cspt_store = ColorStripProcessingTemplateStore(config.storage.color_strip_processing_templates_file)
 sync_clock_manager = SyncClockManager(sync_clock_store)
 
 processor_manager = ProcessorManager(
@@ -74,6 +76,7 @@ processor_manager = ProcessorManager(
     value_source_store=value_source_store,
     audio_template_store=audio_template_store,
     sync_clock_manager=sync_clock_manager,
+    cspt_store=cspt_store,
 )
 
 
@@ -144,6 +147,7 @@ async def lifespan(app: FastAPI):
         auto_backup_engine=auto_backup_engine,
         sync_clock_store=sync_clock_store,
         sync_clock_manager=sync_clock_manager,
+        cspt_store=cspt_store,
     )
 
     # Register devices in processor manager for health monitoring
@@ -281,10 +285,12 @@ async def pwa_service_worker():
 # Middleware: no-cache for static JS/CSS (development convenience)
 @app.middleware("http")
 async def _no_cache_static(request: Request, call_next):
-    response = await call_next(request)
-    if request.url.path.startswith("/static/") and request.url.path.endswith((".js", ".css", ".json")):
+    path = request.url.path
+    if path.startswith("/static/") and path.endswith((".js", ".css", ".json")):
+        response = await call_next(request)
         response.headers["Cache-Control"] = "no-cache, must-revalidate"
-    return response
+        return response
+    return await call_next(request)
 
 # Mount static files
 static_path = Path(__file__).parent / "static"