The SDK's `requireBearerAuth` middleware only converts `InvalidTokenError`
instances to HTTP 401 responses. Generic `Error` instances fall through
as HTTP 500, which prevents clients from detecting authentication failures
and initiating the OAuth refresh/re-auth flow.
This was discovered while building token refresh conformance scenarios —
the mock server was returning 500 for expired/invalid tokens instead of
the expected 401.
Co-authored-by: JD Maturen <70791+jdmaturen@users.noreply.github.com>
Co-authored-by: Cursor <cursoragent@cursor.com>