muster release v5.34.9

Fixed

• A token-exchange server recovers on its own when its token endpoint answers again. A caller’s exchange that timed out, was refused or got a 5xx or a gateway’s HTML page left the server Failed (reason TokenExchangeEndpoint) with no retry, so MusterMCPServerFailed kept paging until a user’s session happened to exchange a token. Now the server is put on the reconnect backoff and each retry probes the token endpoint with the exchange’s client credentials and a subject token no issuer signed: while the probe gets no answer the server stays Failed (never Unreachable), and the first OAuth answer returns it to Awaiting Session, with no caller involved. invalid_client and an unknown connector are still not retried. A Failed server’s Ready message names the next attempt. (#1368)