Fix the findings of the third security audit

- Privileged accounts: the UPN rule also applies when bind_oid is off or
  the account is not bound; privileges are checked on every site of a
  multisite user, include code/HTML capabilities (unfiltered_html,
  plugins, themes, users) and the remembered roles of deactivated
  accounts.
- send_auth_cookies protection also works on WordPress 6.0/6.1.
- Run lock via INSERT IGNORE (atomic), refreshed during long runs; a
  shutdown handler reports fatal errors and frees the lock.
- Deprovisioning only for accounts linked in the current tenant (tenant
  recorded per account; legacy links not found are left alone).
- Safety stop based on the accounts linked before the run; new safety
  stop for removals of administrative roles.
- Disable is idempotent; row-action nonces are bound to the state.
- Profile photos are re-encoded to 240 px (drops EXIF and appended
  data), size-limited while downloading, removed on deactivation;
  index.php guard in the photo folder.
- Privacy exporter and eraser for the copied data.
- One-time migration hardens accounts deactivated by 1.0 and cleans a
  stored certificate bundle; the .cer download is always re-exported.
- Password fields hidden in button-only mode even when the connection
  is broken; settings written non-autoloaded; robust user ID queries.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

includes/class-m365-login.php

@@ -90,6 +90,23 @@ final class M365_Login {
 		}
 
 		add_filter( 'plugin_action_links_' . plugin_basename( M365_LOGIN_FILE ), array( $this, 'action_links' ) );
+		add_action( 'init', array( $this, 'maybe_upgrade' ), 1 );
+	}
+
+	/**
+	 * One-time data migrations after an update.
+	 */
+	public function maybe_upgrade() {
+		$stored = (string) get_option( 'm365_login_version', '1.0.0' );
+		if ( version_compare( $stored, M365_LOGIN_VERSION, '>=' ) ) {
+			return;
+		}
+		update_option( 'm365_login_version', M365_LOGIN_VERSION );
+
+		if ( version_compare( $stored, '1.1.0', '<' ) ) {
+			M365_Login_Sync::harden_legacy_disabled();
+			$this->settings->normalise_stored_certificate();
+		}
 	}
 
 	/**