fixes: tag assign stale body, board placeholder, plugin pending, bucket activate

- Context menu tag toggle reads fresh body from state.cards — was
  overwriting with stale snapshot, dropping existing tags (e.g. #done)
- Board empty-state centered with flex (vertical + horizontal)
- Plugin settings: batch toggles via Apply button, single reload
  instead of one reload per toggle
- New bucket creation activates it directly on the board

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

config.php

@@ -1,7 +1,7 @@
 <?php
 
 define('APP_NAME', 'hyprcrd');
-define('APP_VERSION', '1.4.2');
+define('APP_VERSION', '1.4.3');
 
 // Database path — writable directory, outside webroot
 // DB_PATH / UPLOAD_DIR can be pre-defined by the Electron router for app isolation