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

CONTRIBUTING.md

@@ -9,8 +9,8 @@
 ## Development Setup
 
 ```bash
-git clone https://git.dolgolyov-family.by/alexei.dolgolyov/wled-screen-controller-mixed.git
-cd wled-screen-controller-mixed/server
+git clone https://git.dolgolyov-family.by/alexei.dolgolyov/ledgrab.git
+cd ledgrab/server
 
 # Python environment
 python -m venv venv
@@ -29,7 +29,7 @@ npm run build
 cd server
 export PYTHONPATH=$(pwd)/src   # Linux/Mac
 # set PYTHONPATH=%CD%\src      # Windows
-python -m wled_controller.main
+python -m ledgrab.main
 ```
 
 Open http://localhost:8080 to access the dashboard.
@@ -55,7 +55,7 @@ ruff check src/ tests/
 
 ## Frontend Changes
 
-After modifying any file under `server/src/wled_controller/static/js/` or `static/css/`, rebuild the bundle:
+After modifying any file under `server/src/ledgrab/static/js/` or `static/css/`, rebuild the bundle:
 
 ```bash
 cd server