Activate CLI 0.5.0 channels and canonical agent documentation

[konojunya]

Summary

• Activate the immutable CLI 0.5.0 release in the distribution contract, Aqua lock, and current installation documentation.
• Consume the merged canonical Docs bundle and generated agent skill.
• Mark configuration and doctor commands available; preserve historical release notes and immutable schemas.

Verification

• Published archive provenance, command/JSON smoke, and removed updater behavior pass.
• Fresh isolated Aqua install, init, check, and SVG render pass on macOS ARM64.
• Distribution, Aqua mapping, and skill synchronization tests pass.
• Provider: Document the published Stack CLI 0.5.0 workflow docs#8
• Homebrew activation: Update Stack CLI to 0.5.0 homebrew-tap#4