chore(release): prepare TypeChain 0.2.0

[sjungwon03]

Summary

• Updates TypeChain’s optional TypeMCP peer contract from ^0.2.0 to ^0.3.0 and refreshes the development lockfile to the published @theorvane/type-mcp@0.3.0 artifact.
• Prepares the first release containing the reviewed legacy CommonJS decorator entrypoint as @theorvane/type-chain@0.2.0.
• Updates current user-facing docs and their regression contracts to cite TypeChain 0.2.0 and TypeMCP 0.3.0; historical planning records remain unchanged.

Verification

• npm ci --ignore-scripts --no-audit --no-fund
• npm run verify — Biome, typecheck, 52 tests, build, and package artifacts
• npm run verify:consumer — packed standard consumers and legacy TypeScript/CommonJS consumer
• npm run verify:publish — release readiness plus dry-run package contents
• npm audit --omit=dev --audit-level=low — no production vulnerabilities
• git diff --check

Closes #96

[sjungwon03-ai]

Verified the exact release-preparation head: TypeChain 0.2.0 declares TypeMCP ^0.3.0, lockfile installs 0.3.0, packed standard and legacy CommonJS consumers pass, and required CI is green.