fix(wiki): proxy topology through public gateway

Co-Authored-By: OpenAI Codex <codex@openai.com>

tests/test_guanghan_topology_demo.py

@@ -37,7 +37,8 @@ class GuanghanTopologySourceTests(unittest.TestCase):
         self.assertNotIn("未来西部十字结构", self.html)
 
     def test_page_uses_same_origin_api(self) -> None:
-        self.assertIn("const API_BASE = ''", self.html)
+        self.assertIn("new URL('.', window.location.href).pathname", self.html)
+        self.assertIn("replace(/\\/$/, '')", self.html)
         self.assertNotIn("http://localhost:5000", self.html)
 
     def test_page_uses_database_presentation_payload(self) -> None: