Add concrete value loop guidance

[Teddy-creator]

Summary

• Add Concrete Value Loop rules to Threadsmith skill contracts so next-step recommendations include target, objective, verification, and compact stop conditions.
• Add runtime recommendation metadata for work type, diagnostic budget signals, and concrete next-step details.
• Cover diagnostic budget behavior, value checkpoint routing, and human-centered output fixtures.
• Add the implementation plan as durable repo documentation.

Verification

• npx tsc --noEmit --target ES2022 --module ESNext --moduleResolution Bundler --allowImportingTsExtensions --strict --skipLibCheck packages/runtime/src/nextBestStep.ts
• npm run verify:skill-contract
• npm run test --workspace @threadsmith/runtime
• npm run verify:project-truth
• git diff --check

Notes

• Global installed skill sync was intentionally not performed. Per plan, sync should happen only after this branch/change is accepted or merged and explicitly approved.
• Domain tests were not run because no domain schema/preferences changed.
• Orchestrator tests were not run because autopilot/routing behavior was not changed.

Before / After Shape

Before:
Next phase: do evidence review / continue optimization.

After:
Next: inspect the runtime recommendation fixtures, update the concrete next-step metadata, and run runtime tests; stop if this changes public behavior, provider defaults, release scope, or verification fails.