feat: admin settings page UI/UX pass with WordPress-native patterns

- Header: h1 + logo in a wrapping flex row, hr.wp-header-end before the tabs,
  aria-current on the active tab; own CSS/JS enqueued only on this screen.
- Verbindung: ordered "So verbindest du Claude" steps, copy button (core
  clipboard.js + wp.a11y.speak), Site-Health-style status list, German details.
- Zugriff: roles as form-table fieldset, connections with site date format,
  empty-state row, confirm on revoke; ConnectionUsage records last use via
  WP_Application_Passwords::record_application_password_usage (once a day).
- Tools: plain-language legend, counter as inline notice, groups as core
  postboxes (postbox.js toggles, per-user closed state, summary when closed),
  fixed column widths with new "Art" column, submit above and below.
- Protokoll: site-timezone times with UTC tooltip, result icons, filters with
  labels in the list table nav, retention link to Limits.
- Limits: short labels with units and descriptions; snapshot count hidden but
  preserved.

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

assets/js/admin.js

@@ -0,0 +1,45 @@
+/* Einstellungen → LIT MCP: copy the server URL, collapsible tool groups, filter paging. */
+( function () {
+	'use strict';
+
+	document.addEventListener( 'DOMContentLoaded', function () {
+		var hideTimeout;
+
+		// "URL kopieren" – like WordPress' "Copy URL to clipboard" in the media library.
+		if ( window.ClipboardJS && document.querySelector( '.lit-mcp-copy' ) ) {
+			new window.ClipboardJS( '.lit-mcp-copy' ).on( 'success', function ( event ) {
+				var success = event.trigger.parentNode.querySelector( '.success' );
+
+				event.clearSelection();
+				event.trigger.focus();
+				if ( success ) {
+					clearTimeout( hideTimeout );
+					success.classList.remove( 'hidden' );
+					hideTimeout = setTimeout( function () {
+						success.classList.add( 'hidden' );
+					}, 3000 );
+				}
+				if ( window.wp && window.wp.a11y && window.litMcpAdmin ) {
+					window.wp.a11y.speak( window.litMcpAdmin.copied );
+				}
+			} );
+		}
+
+		// Tool groups: WordPress' own postbox toggles, closed state saved per user.
+		if ( window.postboxes && window.pagenow && document.querySelector( '.lit-mcp-groups' ) ) {
+			window.postboxes.add_postbox_toggles( window.pagenow );
+		}
+
+		// Protokoll: a changed filter starts again on page 1.
+		document.querySelectorAll( '.lit-mcp .tablenav .actions select, .lit-mcp .tablenav .actions input' ).forEach(
+			function ( control ) {
+				control.addEventListener( 'change', function () {
+					var paged = control.form && control.form.querySelector( 'input[name="paged"]' );
+					if ( paged ) {
+						paged.value = '1';
+					}
+				} );
+			}
+		);
+	} );
+}() );