fix(cli): prevent tar path traversal in plugin install

[kshirajahere]

Summary

Harden mofa plugin install tar extraction to prevent archive path traversal attempts from writing outside the plugin destination directory.

Related Issues

Closes #1323

Related to #461

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Context

install_from_url() accepts remote .tar.gz archives and previously extracted them via tar::Archive::unpack(dest_dir). That broad extraction path does not provide explicit per-entry confinement logic in the installer and is risky in a supply-chain-sensitive code path.

This change applies explicit entry-level extraction checks so malicious archive entries cannot escape the plugin directory.

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Changes

• Replaced bulk tar extraction in extract_tar_gz() with per-entry iteration.
• Switched to entry.unpack_in(dest_dir) for destination confinement.
• Return a dedicated plugin error when an entry escape attempt is detected.
• Added a regression test that builds a crafted traversal-style tar entry and verifies extraction is rejected.

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How you Tested

1. cargo fmt --package mofa-cli
2. cargo test -p mofa-cli test_extract_tar_gz_rejects_path_traversal -- --nocapture
3. cargo test -p mofa-cli test_install_invalid_plugin_structure

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Screenshots / Logs (if applicable)

Key results:

• test_extract_tar_gz_rejects_path_traversal ... ok
• test_install_invalid_plugin_structure ... ok

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Breaking Changes

• No breaking changes
• Breaking change (describe below)

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Checklist

Code Quality

• Code follows Rust idioms and project conventions
• cargo fmt run
• cargo clippy passes without warnings

Testing

• Tests added/updated
• cargo test passes locally without any error

Documentation

• Public APIs documented
• README / docs updated (if needed)

PR Hygiene

• PR is small and focused (one logical change)
• Branch is up to date with main
• No unrelated commits
• Commit messages explain why, not only what

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Deployment Notes (if applicable)

No migration required.

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Additional Notes for Reviewers

This PR intentionally limits scope to .tar.gz extraction hardening in CLI plugin install. Zip extraction already uses enclosed-name handling and is unchanged.

[kshirajahere]

@mugiwaraluffy56 please review :)