Add multi-announcement management system

- Update inc/announcements.php to support listing, fetching by ID, toggling, and deleting multiple announcements
- Upgrade admin/index.php to an announcement management view with data table, status indicators, and create/edit sub-views
- Add admin table and action styles to styles.css without using inline style blocks
- Update index.php to render all currently active banner and hours announcements dynamically

styles.css

@@ -1159,4 +1159,73 @@
     background: rgba(138, 115, 74, 0.2);
     border: 1px solid var(--rule);
     color: var(--ink-muted);
+  }
+
+  /* admin table & list actions */
+  .admin-table-wrap {
+    overflow-x: auto;
+    margin-top: 1rem;
+  }
+
+  .admin-table {
+    width: 100%;
+    border-collapse: collapse;
+    font-size: 0.92rem;
+  }
+
+  .admin-table th,
+  .admin-table td {
+    padding: 0.85rem 0.75rem;
+    text-align: left;
+    border-bottom: 1px solid var(--rule);
+    vertical-align: middle;
+  }
+
+  .admin-table th {
+    font-family: var(--font-mono);
+    font-size: 0.72rem;
+    letter-spacing: 0.12em;
+    text-transform: uppercase;
+    color: var(--gold);
+    font-weight: 500;
+  }
+
+  .admin-table tr:last-child td {
+    border-bottom: none;
+  }
+
+  .admin-table-actions {
+    display: inline-flex;
+    gap: 0.5rem;
+    align-items: center;
+    flex-wrap: wrap;
+  }
+
+  .btn-sm {
+    padding: 0.4rem 0.8rem;
+    font-size: 0.75rem;
+    line-height: 1.2;
+  }
+
+  .btn-danger {
+    background: rgba(180, 50, 40, 0.15);
+    border: 1px solid rgba(220, 80, 60, 0.5);
+    color: #ff9d9d;
+  }
+
+  .btn-danger:hover {
+    background: rgba(220, 60, 50, 0.3);
+    border-color: #ff6e6e;
+    color: #fff;
+  }
+
+  .empty-state {
+    text-align: center;
+    padding: 3rem 1.5rem;
+    color: var(--ink-muted);
+  }
+
+  .empty-state p {
+    font-size: 0.95rem;
+    margin-bottom: 1.25rem;
   }