Adds a two-step account-deletion UX: "Delete Account" button in the
Settings sync section (visible only when server backend is configured)
fires DeleteAccountRequestEvent → SyncSetupPlugin opens a confirmation
modal. "Delete Forever" spawns an async delete_account task; on success
SyncLogoutRequestEvent clears local credentials and resets the backend.
Errors surface via InfoToast.
Also splits handle_settings_buttons into handle_settings_buttons +
handle_sync_buttons to stay within Bevy's 16-parameter system limit.
Sync buttons (Sync Now, Connect, Disconnect, Delete Account) are now
handled in the dedicated handle_sync_buttons system.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
funman300
272d31f851