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/test_processor_manager.py

@@ -2,7 +2,7 @@
 
 import pytest
 
-from wled_controller.core.processing.processor_manager import (
+from ledgrab.core.processing.processor_manager import (
     ProcessorDependencies,
     ProcessorManager,
 )
@@ -233,7 +233,7 @@ def test_get_target_metrics(processor_manager):
 
 def test_target_type_detection(processor_manager):
     """Test target type detection via processor instances."""
-    from wled_controller.core.processing.wled_target_processor import WledTargetProcessor
+    from ledgrab.core.processing.wled_target_processor import WledTargetProcessor
 
     processor_manager.add_device(
         device_id="test_device",