feat(header): add favicon logo symbol and update brand text

- Add animated agent network favicon logo symbol to header brand link
- Update brand typography to ANL and AI Agent Networking LAB
- Update E2E test assertions for the updated header branding

refer_landing_page/tests/e2e_test_suite.py

@@ -33,8 +33,8 @@ class TestANLHomepageE2E(unittest.TestCase):
         html = self.read_html("index.html")
         
         # 1. Brand & Header titles
-        self.assertIn("AI 에이전트 네트워크 연구실", html)
-        self.assertIn("AI Agent Networking Lab (ANL)", html)
+        self.assertIn("ANL", html)
+        self.assertIn("AI Agent Networking LAB", html)
         
         # 2. Research Areas keywords
         self.assertIn("Quick UDP Internet Connection (QUIC)", html)