fix(tests): match chat-app title assertion to renamed Agent UI title (amd#1927)

"Test Electron Framework" has been red on main and every PR since
2026-06-22: amd#1750 renamed the Agent UI window title to "GAIA Agent UI",
but `test_electron_chat_app.js` still expects `<title>GAIA</title>`.
This aligns the assertion with the actual title — the same suite already
asserts `displayName: 'GAIA Agent UI'`, so the rename was clearly
intentional. Unblocks the check on Dependabot PRs amd#1803, amd#1805, amd#1861
among others.

## Test plan
- [x] `npx jest test_electron_chat_app.js` locally: 196/196 pass with
the fix (previously 195/196)
- [ ] "Test Electron Framework" green on this PR

Co-authored-by: Tomasz Iniewicz <tomasz@iniewicz.com>

Author: itomek

tests/electron/test_electron_chat_app.js

@@ -166,7 +166,7 @@ describe('Chat App Integration', () => {
     });
 
     it('should have GAIA title', () => {
-      expect(htmlContent).toContain('<title>GAIA</title>');
+      expect(htmlContent).toContain('<title>GAIA Agent UI</title>');
     });
 
     it('should have React root div', () => {