Some MCP servers place .well-known metadata at the appended path
(e.g. /v1/.well-known/oauth-protected-resource) instead of the
RFC 9728 compliant inserted path. Now tries the RFC-compliant URL
first and falls back to the appended form.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>