sandbox@3.1.1

Patch Changes

• Fix sandbox connect hanging or failing on a stopped/resumed sandbox. The interactive shell now surfaces attach() failures instead of swallowing them once the connection handshake lands, always stops the spinner on teardown (so a failure can no longer hang the process), and includes the in-sandbox server's stderr when the interactive server exits early. The in-sandbox vc-interactive-server also health-checks a reused server before trusting a leftover config file, so a stale /tmp/vercel/interactive/config.json restored from a snapshot no longer causes it to connect to a dead socket. (#215)