Release Proofline v2.0.2

[thangldw]

Summary

• align Python, web, desktop, CI, and plugin version surfaces to 2.0.2
• publish trilingual v2.0.2 release documentation for post-v2.0.1 hardening
• fail release qualification on stale Cargo.lock and exclude unsigned desktop installers from GitHub Release assets

Verification

• 562 Python tests
• 67 web tests
• 2 Playwright E2E tests
• Ruff, format, web build, bundled-web sync, egress checks
• package/review/attestation conformance
• pip-audit and npm audit
• desktop debug build
• wheel, sdist, and skills-only plugin ZIP qualification

Boundaries

• no dependency-major updates
• no real-team pilot claim
• no unsigned/notarization-free desktop artifacts published as release-grade
• preserves immutable v2.0.1 evidence and artifacts