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/scripts/start-server-background.vbs

@@ -2,6 +2,6 @@ Set WshShell = CreateObject("WScript.Shell")
 Set FSO = CreateObject("Scripting.FileSystemObject")
 ' Get parent folder of scripts folder (server root)
 WshShell.CurrentDirectory = FSO.GetParentFolderName(FSO.GetParentFolderName(WScript.ScriptFullName))
-WshShell.Run "python -m wled_controller", 0, False
+WshShell.Run "python -m ledgrab", 0, False
 Set FSO = Nothing
 Set WshShell = Nothing