- Generate lan-client/precons.js from precon-decks/precon-index.json so PRECON_DATA is always available for local/offline mode - Add scripts/generate-precons-js.js for re-generation - Fix _loadBackendPrecons() to actually re-render the precon tab UI when backend precons load (was only updating status indicator text) Fixes the empty precon dropdown and 'No precon data loaded' message.