feat(v3): bundle React dashboard and global nyx CLI command

[ptkvaibhav]

Summary

• explain the problem addressed
• explain the user-facing behavior change

Checklist

• scan scope remains limited to approved directories
• no rename, move, or delete occurs without an approval path
• duplicate or irrelevance logic includes evidence
• tests or verification commands were run
• docs were updated if the workflow changed

Verification

npm run check:quality
npm run check:security
npm test
npm run test:smoke

Risks

• list edge cases, residual risks, or missing follow-up work