add optional web search functionality with UI updates and backend integration

src/services/chatMessageHelpers.js

@@ -1,3 +1,10 @@
+import {normalizeSources} from "./webSearchService.js";
+
+export function parseSources(value) {
+    try { return normalizeSources(typeof value === "string" ? JSON.parse(value) : value); }
+    catch { return []; }
+}
+
 export const retryStylePrompts = Object.freeze({
     shorter: "Rewrite the assistant reply to be shorter and tighter while preserving its meaning.",
     direct: "Rewrite the assistant reply to be more direct and less padded.",
@@ -34,6 +41,7 @@ export function formatChatMessage(row) {
         id: row.id,
         role: row.role,
         content: row.content,
+        ...(row.sources ? {sources: parseSources(row.sources)} : {}),
         modelName: row.model_name || null,
         retryVariants,
         retryActiveIndex,