fix(ui): persist Lighthouse chat URL before notifications

ui/app/(prowler)/lighthouse/_components/chat/lighthouse-v2-chat-page.test.tsx

@@ -3,6 +3,7 @@ import userEvent from "@testing-library/user-event";
 import { type ReactNode } from "react";
 import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
 
+import { LIGHTHOUSE_V2_SESSIONS_CHANGED_EVENT } from "@/app/(prowler)/lighthouse/_lib/session-events";
 import type {
   LighthouseV2Configuration,
   LighthouseV2Message,
@@ -241,6 +242,37 @@ describe("LighthouseV2ChatPage", () => {
     replaceStateSpy.mockRestore();
   });
 
+  it("updates the URL before notifying session history listeners", async () => {
+    // Given
+    const user = userEvent.setup();
+    const notifiedUrls: string[] = [];
+    const recordCurrentUrl = () => {
+      notifiedUrls.push(`${window.location.pathname}${window.location.search}`);
+    };
+    window.addEventListener(
+      LIGHTHOUSE_V2_SESSIONS_CHANGED_EVENT,
+      recordCurrentUrl,
+    );
+    renderPage();
+
+    try {
+      // When
+      await user.type(
+        screen.getByRole("textbox", { name: "Message" }),
+        ["Summarize findings", "{Enter}"].join(""),
+      );
+
+      // Then
+      await waitFor(() => expect(notifiedUrls.length).toBeGreaterThan(0));
+      expect(notifiedUrls[0]).toBe("/lighthouse?session=session-1");
+    } finally {
+      window.removeEventListener(
+        LIGHTHOUSE_V2_SESSIONS_CHANGED_EVENT,
+        recordCurrentUrl,
+      );
+    }
+  });
+
   it("subscribes to the stream before sending the message (no replay buffer)", async () => {
     // Given
     const user = userEvent.setup();

ui/app/(prowler)/lighthouse/_components/chat/lighthouse-v2-chat-page.tsx

@@ -202,16 +202,12 @@ export function LighthouseV2ChatPage({
       return null;
     }
 
-    setActiveSessionId(result.data.id);
-    notifyLighthouseV2SessionsChanged();
     // Update the URL in place (not router.push) so the force-dynamic server
     // component is NOT re-run mid-submit. A re-run would change `key` in
     // page.tsx and remount this component, tearing down the open EventSource.
-    window.history.replaceState(
-      null,
-      "",
-      `/lighthouse?session=${encodeURIComponent(result.data.id)}`,
-    );
+    replaceLighthouseV2SessionUrl(result.data.id);
+    setActiveSessionId(result.data.id);
+    notifyLighthouseV2SessionsChanged();
     return result.data.id;
   };
 
@@ -321,7 +317,7 @@ export function LighthouseV2ChatPage({
       setIsSubmitting(false);
       setLastSubmittedText(null);
       setStreamState(createInitialLighthouseV2StreamState());
-      window.history.replaceState(null, "", "/lighthouse");
+      replaceLighthouseV2SessionUrl(null);
     };
 
     window.addEventListener(LIGHTHOUSE_V2_NEW_CHAT_EVENT, resetToNewChat);
@@ -393,3 +389,11 @@ export function LighthouseV2ChatPage({
     </Card>
   );
 }
+
+function replaceLighthouseV2SessionUrl(sessionId: string | null) {
+  const url = sessionId
+    ? `/lighthouse?session=${encodeURIComponent(sessionId)}`
+    : "/lighthouse";
+
+  window.history.replaceState(window.history.state, "", url);
+}