Release 0.2.0

[markm39]

Summary

• Bumps @mathnotes/mobile-ink to 0.2.0.
• Updates the iOS podspec version to match the npm package version.
• Adds changelog notes for the Ganesh default renderer and benchmark tooling.

Test plan

• npm run validate
• Simplify review: release metadata only; no maintainability findings.
• Security review: release metadata only; no auth, secret, or sensitive-data findings.

Publish note

Npm publish still requires npm authentication from the release machine. npm whoami currently returns 401 locally, so publish/tag/release should happen after npm login is available.