Harden DevMap 0.1.0 for npm release

[itsflaid]

Summary

• expand npm package metadata and the package-facing README
• add the 0.1.0 changelog and documented release procedure
• use package.json as the single source for CLI and doctor versions
• synchronize the PRD launch checklist and version roadmap
• document benchmarking and external feedback as post-launch beta validation

Verification

• pnpm test:cli (65/65)
• pnpm build:cli
• pnpm build:web
• pnpm test:package-e2e
• npm pack ./packages/cli --dry-run --json
• node packages/cli/dist/index.js --version (0.1.0)
• git diff --check
• secret scan

Closes #21