Add LLM endpoints, web frontend, and rate limiting config

- Added OpenAI-compatible LLM endpoints to API backend - Introduced web
frontend with Jinja2 templates and static assets - Implemented API proxy
routes in web service - Added sample db.json data for items, users,
orders, reviews, categories, llm_requests - Updated ADC and Helm configs
for separate AI and standard rate limiting - Upgraded FastAPI, Uvicorn,
and added httpx, Jinja2, python-multipart dependencies - Added API
configuration modal and client-side JS for web app

web/static/js/app.js

@@ -0,0 +1,123 @@
+// Global API configuration
+const DEFAULT_API_BASE = "/api";
+const API_BASE_KEY = "api_base_url";
+
+// Get API base URL from localStorage or use default
+function getApiBaseUrl() {
+  return localStorage.getItem(API_BASE_KEY) || DEFAULT_API_BASE;
+}
+
+// Set API base URL
+function setApiBaseUrl(url) {
+  localStorage.setItem(API_BASE_KEY, url);
+}
+
+// Export for global access
+window.API_BASE = getApiBaseUrl();
+
+// API Configuration Modal Functions
+function openApiConfig(event) {
+  if (event) event.preventDefault();
+
+  const modal = document.getElementById("api-config-modal");
+  const input = document.getElementById("api-base-url");
+  const currentUrl = document.getElementById("current-api-url");
+
+  input.value = getApiBaseUrl();
+  currentUrl.textContent = getApiBaseUrl();
+  modal.style.display = "block";
+}
+
+function closeApiConfig() {
+  const modal = document.getElementById("api-config-modal");
+  modal.style.display = "none";
+}
+
+function saveApiConfig() {
+  const input = document.getElementById("api-base-url");
+  const url = input.value.trim();
+
+  if (!url) {
+    alert("Please enter a valid API base URL");
+    return;
+  }
+
+  // Remove trailing slash if present
+  const cleanUrl = url.endsWith("/") ? url.slice(0, -1) : url;
+
+  setApiBaseUrl(cleanUrl);
+  window.API_BASE = cleanUrl;
+
+  showNotification("API configuration saved. Reloading page...", "success");
+
+  setTimeout(() => {
+    window.location.reload();
+  }, 1000);
+}
+
+function resetApiConfig() {
+  if (confirm("Reset API configuration to default (/api)?")) {
+    setApiBaseUrl(DEFAULT_API_BASE);
+    window.API_BASE = DEFAULT_API_BASE;
+
+    showNotification("API configuration reset. Reloading page...", "success");
+
+    setTimeout(() => {
+      window.location.reload();
+    }, 1000);
+  }
+}
+
+// Close modal when clicking outside
+window.onclick = function (event) {
+  const modal = document.getElementById("api-config-modal");
+  if (event.target === modal) {
+    closeApiConfig();
+  }
+};
+
+// Utility functions
+function showNotification(message, type = "info") {
+  console.log(`[${type.toUpperCase()}] ${message}`);
+  // Could be extended with toast notifications
+}
+
+function formatDate(dateString) {
+  const date = new Date(dateString);
+  return date.toLocaleDateString() + " " + date.toLocaleTimeString();
+}
+
+function formatPrice(price) {
+  return new Intl.NumberFormat("en-US", {
+    style: "currency",
+    currency: "USD",
+  }).format(price);
+}
+
+// API call wrapper
+async function apiCall(endpoint, options = {}) {
+  try {
+    const response = await fetch(`${API_BASE}${endpoint}`, {
+      ...options,
+      headers: {
+        "Content-Type": "application/json",
+        ...options.headers,
+      },
+    });
+
+    if (!response.ok) {
+      throw new Error(`HTTP ${response.status}: ${response.statusText}`);
+    }
+
+    return await response.json();
+  } catch (error) {
+    showNotification(error.message, "error");
+    throw error;
+  }
+}
+
+// Export for use in templates
+window.apiCall = apiCall;
+window.showNotification = showNotification;
+window.formatDate = formatDate;
+window.formatPrice = formatPrice;