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/core/router.js

@@ -0,0 +1,134 @@
+/**
+ * Hash-based SPA router.
+ * Routes map to lazy-loaded page modules (ES modules with mount/unmount).
+ *
+ * Each page module must export:
+ *   mount(container, ctx): void | Promise<void>
+ *   unmount(): void
+ *   onRouteParams?(params): void  [optional]
+ *
+ * The router guarantees unmount() is called before switching pages.
+ */
+
+import { updateDOM as updateI18n, t } from './i18n.js';
+
+/** @type {Map<string, () => Promise<{mount, unmount, onRouteParams?}>>} */
+const _routes = new Map();
+let _currentModule = null;
+let _currentRoute = null;
+let _container = null;
+let _notFoundHandler = null;
+
+/**
+ * Register a route.
+ * @param {string} path - hash path without '#', e.g. '/dashboard'
+ * @param {Function} loader - async function returning the module, e.g. () => import('../pages/dashboard.js')
+ */
+export function route(path, loader) {
+  _routes.set(path, loader);
+}
+
+/**
+ * Set a fallback handler for unknown routes.
+ * @param {Function} handler - (container, hash) => void
+ */
+export function setNotFound(handler) {
+  _notFoundHandler = handler;
+}
+
+/**
+ * Initialize the router.
+ * @param {HTMLElement} container - the element to mount pages into (e.g. #app)
+ */
+export function init(container) {
+  _container = container;
+  window.addEventListener('hashchange', () => _resolve());
+  // Initial route
+  _resolve();
+}
+
+/**
+ * Force remount of the current route (used for i18n/theme refresh).
+ */
+export function reloadCurrent() {
+  _resolve(true);
+}
+
+/**
+ * Programmatic navigation.
+ * @param {string} path - e.g. '/dashboard'
+ */
+export function navigate(path) {
+  window.location.hash = '#' + path;
+}
+
+/**
+ * Get current route path.
+ */
+export function currentRoute() {
+  return _currentRoute;
+}
+
+/* -- Internal -- */
+
+async function _resolve(force = false) {
+  const hash = window.location.hash.slice(1) || '/dashboard'; // default
+  const [path, queryStr] = hash.split('?');
+  const params = Object.fromEntries(new URLSearchParams(queryStr || ''));
+
+  // If same route, just update params
+  if (!force && path === _currentRoute && _currentModule?.onRouteParams) {
+    _currentModule.onRouteParams(params);
+    return;
+  }
+
+  // Unmount previous
+  if (_currentModule) {
+    try {
+      _currentModule.unmount();
+    } catch (err) {
+      console.error(`[Router] Error unmounting ${_currentRoute}:`, err);
+    }
+    _currentModule = null;
+  }
+
+  // Clear container
+  _container.innerHTML = '';
+  _currentRoute = path;
+
+  // Find matching route
+  const loader = _routes.get(path);
+  if (!loader) {
+    if (_notFoundHandler) {
+      _notFoundHandler(_container, path);
+    } else {
+      _container.textContent = t('router.notFound', { path });
+    }
+    return;
+  }
+
+  // Loading indicator
+  _container.setAttribute('aria-busy', 'true');
+
+  try {
+    const mod = await loader();
+    _currentModule = mod;
+
+    // Mount the page
+    await mod.mount(_container, { params, navigate });
+
+    // Update i18n labels in the newly mounted content
+    updateI18n(_container);
+
+    // Pass route params if handler exists
+    if (mod.onRouteParams) {
+      mod.onRouteParams(params);
+    }
+
+  } catch (err) {
+    console.error(`[Router] Error loading ${path}:`, err);
+    _container.textContent = t('router.errorLoading', { message: err.message });
+  } finally {
+    _container.removeAttribute('aria-busy');
+  }
+}