MoveMailbox v0.4.0-preview

MoveMailbox v0.4.0-preview

This preview hardens the hosted worker and operator recovery path:

• portable AGENTS.md and two-computer GitHub handoff instructions;
• real Mail-in-a-Box ENOSPC and worker crash recovery after native copy;
• authenticated worker health checks for safe token rotation;
• coordinated recipient-key/token rotation drill with fail-closed mismatch tests;
• encrypted age metadata backup, atomic object commit and fresh-volume restore;
• rejection of truncated/corrupt archives, links, traversal, oversized members
  and incomplete uploads;
• Windows, Linux and macOS preview packages with SHA-256 checksums.

This is not a production launch. The encrypted object-store test is local, not an
off-site provider proof; real VPS egress, HTTPS, KMS/secret management, retention,
external security review and payment/account flows remain deployment gates.

The archive contains metadata only. It does not bundle imapsync or mailbox data.