New commands

avocado save and avocado load

Export and import portable build state archives for sharing builds across machines or archiving known-good states:

# Save current build state to an archive
avocado save -o build-state.tar.zst

# Load a build state archive on another machine
avocado load build-state.tar.zst

Archives include sysroots, stamps, and build artifacts — everything needed to resume work without re-running avocado install and avocado build.

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New features

Auto-register QEMU binfmt for cross-arch SDK emulation

When using --sdk-arch to run an SDK container for a different architecture (e.g., building for aarch64 on an x86-64 host), the CLI now automatically registers the required QEMU binfmt handler if it is not already present. This eliminates the manual docker run --privileged binfmt setup step.

Per-part SHA256 checksums for multipart uploads

Each part of a multipart upload now includes a SHA256 checksum that is verified server-side, ensuring data integrity for every chunk — not just the final assembled artifact.

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Improvements

• Replaced print_and_exit() calls with proper Err(anyhow!(...)) error propagation, improving error handling consistency and enabling better error context in nested operations.