chore: prep v0.2.0 release and upgrade Convex

[bntvllnt]

Summary

• upgrade Convex support to convex@^1.36.1 and convex-test@^0.0.50
• prep the package for the 0.2.0 release by bumping package.json, refreshing CHANGELOG.md, and syncing public docs
• align the public client wrapper/types with the documented API (limit support on list()/listByTag(), no stale retryAfter field)
• refresh llms.txt / llms-full.txt and make preversion use build-only validation instead of auth-gated Convex codegen
• mark stale audit/roadmap docs as historical so they no longer read like current release guidance

Validation

• pnpm generate:llms
• pnpm lint
• pnpm build
• pnpm test
• pnpm typecheck

Notes

• Local lint validation temporarily moved the untracked .worktrees/ directory out of the repo during the run so ESLint only evaluated tracked project files.
• GitHub repo description/topics still mention built-in rate limiting; I left repo metadata unchanged in this PR.