feat(poc4): route UI through HMM MCP

poc4_active_source_20260714/apps/poc4/mcp_discovery_ui.py

@@ -1452,6 +1452,7 @@ div[data-testid="stFormSubmitButton"] > button[data-testid="stBaseButton-primary
 class McpServer:
     server_id: str
     endpoint_url: str
+    auth_token_env: str
     default_tool: str
     tool_allowlist: tuple[str, ...]
     router_model_profile: str
@@ -3691,6 +3692,7 @@ def load_mcp_servers(path: Path = MCP_SERVERS_FILE) -> tuple[list[McpServer], in
         server = McpServer(
             server_id=server_id,
             endpoint_url=endpoint_url,
+            auth_token_env=str(item.get("auth_token_env") or "").strip(),
             default_tool=str(item.get("default_tool") or PREFERRED_TOOL).strip(),
             tool_allowlist=allowlist,
             router_model_profile=str(
@@ -6964,6 +6966,9 @@ def main() -> None:
         return
 
     default_router_model_profile = servers[default_server_index].router_model_profile
+    configured_mcp_bearer = _runtime_env_value(
+        servers[default_server_index].auth_token_env
+    )
     query_model_profile_key = "poc4_query_model_profile"
     default_query_model_profile = DEFAULT_QUERY_MODEL_PROFILE
     try:
@@ -7053,7 +7058,12 @@ def main() -> None:
             )
         else:
             selected_token_preset = None
-        if selected_token_preset is not None:
+        if configured_mcp_bearer:
+            # The HMM MCP gateway uses its own server-side credential.  VPD user
+            # tokens remain UI context only and must never be forwarded to it.
+            st.caption("MCP 인증: 서버 관리 토큰 적용")
+            manual_bearer_token = ""
+        elif selected_token_preset is not None:
             manual_bearer_token = st.text_input(
                 "Bearer token",
                 value=selected_token_preset.token,
@@ -7068,7 +7078,7 @@ def main() -> None:
                 type="default",
                 key="poc4_manual_bearer_token",
             )
-        bearer_token = (
+        bearer_token = configured_mcp_bearer or (
             selected_token_preset.token
             if selected_token_preset is not None
             else manual_bearer_token