Add RLUtils class for managing RL/AI dashboard endpoints

- Implemented methods for fetching AI stats, training history, and recent experiences.
- Added functionality to set operation mode (MANUAL, AUTO, AI) with appropriate handling.
- Included helper methods for querying the database and sending JSON responses.
- Integrated model metadata extraction for visualization purposes.

web/js/pages/_stub.js

@@ -0,0 +1,41 @@
+/**
+ * Page module stub template.
+ * Copy this file and rename for each new page.
+ * Replace PAGE_NAME, endpoint, and build logic.
+ */
+
+import { ResourceTracker } from '../core/resource-tracker.js';
+import { api, Poller } from '../core/api.js';
+import { el, $, setText, escapeHtml } from '../core/dom.js';
+import { t } from '../core/i18n.js';
+
+const PAGE_NAME = 'stub';
+let tracker = null;
+let poller = null;
+
+export async function mount(container) {
+  tracker = new ResourceTracker(PAGE_NAME);
+  container.appendChild(el('div', { class: `${PAGE_NAME}-container` }, [
+    el('h2', { 'data-i18n': `nav.${PAGE_NAME}` }, [t(`nav.${PAGE_NAME}`)]),
+    el('div', { id: `${PAGE_NAME}-content` }, [t('common.loading')]),
+  ]));
+
+  // Initial fetch
+  await refresh();
+
+  // Optional poller (visibility-aware)
+  // poller = new Poller(refresh, 10000);
+  // poller.start();
+}
+
+export function unmount() {
+  if (poller) { poller.stop(); poller = null; }
+  if (tracker) { tracker.cleanupAll(); tracker = null; }
+}
+
+async function refresh() {
+  // try {
+  //   const data = await api.get('/endpoint', { timeout: 8000 });
+  //   paint(data);
+  // } catch (err) { console.warn(`[${PAGE_NAME}]`, err.message); }
+}