pub fn authorization_server_metadata(
server_url: &str,
config: &OAuthConfig,
) -> ValueExpand description
Build the Authorization Server Metadata JSON response (RFC 8414).
Returned at GET /.well-known/oauth-authorization-server so MCP
clients can discover the authorization and token endpoints.
issuer defaults to server_url, the origin this document is served from,
as RFC 8414 3.3 requires. The upstream OAuthConfig::issuer remains the
token issuer and is still what inbound JWT iss claims are validated
against - the two are deliberately different. See
OAuthConfig::authorization_server_metadata_issuer for the legacy
opt-out.