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/dom.js

@@ -0,0 +1,97 @@
+/**
+ * Safe DOM utilities — avoids innerHTML with untrusted content.
+ */
+import { trLoose } from './i18n.js';
+
+/**
+ * Create an element with attributes and children (safe, no innerHTML).
+ * @param {string} tag
+ * @param {object} attrs - className, style, data-*, event handlers (onclick, etc.)
+ * @param {Array} children - strings or HTMLElements
+ * @returns {HTMLElement}
+ */
+export function el(tag, attrs = {}, children = []) {
+  const node = document.createElement(tag);
+  for (const [k, v] of Object.entries(attrs)) {
+    if (v == null || v === false) continue;
+    if (k === 'class' || k === 'className') node.className = v;
+    else if (k === 'style' && typeof v === 'string') node.style.cssText = v;
+    else if (k === 'style' && typeof v === 'object') Object.assign(node.style, v);
+    else if (k.startsWith('on') && typeof v === 'function') {
+      node.addEventListener(k.slice(2).toLowerCase(), v);
+    }
+    else node.setAttribute(k, String(v));
+  }
+  for (const child of (Array.isArray(children) ? children : [children])) {
+    if (child == null || child === false) continue;
+    if (typeof child === 'string' || typeof child === 'number') {
+      node.appendChild(document.createTextNode(String(child)));
+    } else if (child instanceof Node) {
+      node.appendChild(child);
+    }
+  }
+  return node;
+}
+
+/**
+ * Shorthand selectors.
+ */
+export const $ = (s, root = document) => root.querySelector(s);
+export const $$ = (s, root = document) => Array.from(root.querySelectorAll(s));
+
+/**
+ * Escape HTML entities to prevent XSS when rendering untrusted text.
+ * @param {string} str
+ * @returns {string}
+ */
+export function escapeHtml(str) {
+  const div = document.createElement('div');
+  div.appendChild(document.createTextNode(str));
+  return div.innerHTML;
+}
+
+/**
+ * Set text content safely (never innerHTML with untrusted data).
+ * @param {HTMLElement} el
+ * @param {string} text
+ */
+export function setText(el, text) {
+  if (el) el.textContent = text;
+}
+
+/**
+ * Show a toast notification.
+ * @param {string} message - plain text (safe)
+ * @param {number} duration - ms
+ * @param {string} type - 'info' | 'success' | 'error' | 'warning'
+ */
+export function toast(message, duration = 2600, type = 'info') {
+  const container = document.getElementById('toasts');
+  if (!container) return;
+
+  const t = el('div', { class: `toast toast-${type}` }, [trLoose(String(message))]);
+  container.appendChild(t);
+
+  setTimeout(() => {
+    t.style.transition = 'transform .2s ease, opacity .2s';
+    t.style.transform = 'translateY(10px)';
+    t.style.opacity = '0';
+    setTimeout(() => t.remove(), 220);
+  }, duration);
+}
+
+/**
+ * Empty a container safely.
+ * @param {HTMLElement} container
+ */
+export function empty(container) {
+  while (container.firstChild) container.removeChild(container.firstChild);
+}
+
+export function confirmT(message) {
+  return window.confirm(trLoose(String(message)));
+}
+
+export function promptT(message, defaultValue = '') {
+  return window.prompt(trLoose(String(message)), defaultValue);
+}