List connected accounts for an MCP configuration

Returns the connected account state for each connection in the MCP configuration for the given user identifier. When include_auth_link is true, creates connected accounts on the fly if they do not exist and returns a fresh authentication link per connection. When include_auth_link is false or omitted, returns the current status of existing connected accounts only — no accounts are created and authentication_link is always empty. Authentication links are only present when the connection has an associated key; if the connection has no key, authentication_link is empty regardless of include_auth_link.