refactor: rename project to LedGrab, split HA integration into separate repo

- Rename Python package: wled_controller -> ledgrab
- Rename env var prefix: WLED_ -> LEDGRAB_ (with auto-migration for old vars)
- Rename localStorage key: wled_api_key -> ledgrab_api_key (with migration)
- Rename HA integration domain: wled_screen_controller -> ledgrab
- Update all imports, build scripts, Docker, installer, config, docs
- Remove HA integration (moved to ledgrab-haos-integration repo)
- Remove hacs.json (belongs in HA repo now)
- Add startup warning for users with old WLED_ env vars
- All tests pass (715/715), ruff clean, tsc clean, frontend builds

server/tests/api/test_audio_processing_templates_api.py

@@ -2,10 +2,10 @@
 
 import pytest
 
-from wled_controller.config import get_config
+from ledgrab.config import get_config
 
 # Ensure audio filters registered
-import wled_controller.core.audio.filters  # noqa: F401
+import ledgrab.core.audio.filters  # noqa: F401
 
 _config = get_config()
 _api_key = next(iter(_config.auth.api_keys.values()), "")
@@ -16,7 +16,7 @@ AUTH = {"Authorization": f"Bearer {_api_key}"} if _api_key else {}
 def client():
     """Provide a TestClient with lifespan (startup/shutdown) properly triggered."""
     from fastapi.testclient import TestClient
-    from wled_controller.main import app
+    from ledgrab.main import app
 
     with TestClient(app) as c:
         yield c