fix(mcpb): pass config_path parameter to load_config() in async_main()

Critical bug fix: When CIDX_SERVER_URL is set via environment variable,
the code correctly determines config_path should be DEFAULT_CONFIG_PATH,
but fails to pass it to load_config(). This prevents bearer_token and
refresh_token from being loaded from the config file.

Fix: Add config_path parameter to load_config() call on line 177.

This enables the config file to be read properly when env vars are set,
allowing automatic token refresh to work correctly.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: Test

src/code_indexer/mcpb/bridge.py

@@ -174,7 +174,7 @@ async def async_main():  # pragma: no cover
             config_path = DEFAULT_CONFIG_PATH
 
         # Load configuration
-        config = load_config(use_env=True)
+        config = load_config(config_path=config_path, use_env=True)
 
         # Create and run bridge
         bridge = Bridge(config, config_path=config_path)