RoadmapSmith Validate

Use this command when the user wants per-task evidence status without mutating the roadmap.

Required behavior

1. Prefer the local engine inside this repository:
   • node roadmap-skill/bin/cli.js validate --json --project-root .
   • on this Windows machine, prefer C:\Program Files\nodejs\node.exe roadmap-skill/bin/cli.js validate --json --project-root . if node is not in PATH
2. Otherwise prefer roadmapsmith validate --json --project-root ..
3. Treat this command as CLI-backed and non-mutating.