fix(cli): auth session list reports unreachable servers and ignores stale runtime files

Print the unreachable-server error on stderr instead of exiting silently,
treat a runtime file whose recorded process is gone as no running server,
and give the temporary access:read session a one-minute TTL.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
10cd74a573Julius Marminge committed on 10/22/2026, 2:16:36 AMparent528b93d
2 files changedLine totals unavailable