[rig-sampler] docs(s.unknown): add @example and fix header comment for description-form usage

[github-actions]

Sample run: src/samples/09-classify-issue.ts

This sample defines an agent with two s.enum output fields (label and confidence). It ran cleanly with 0 repair turns — the schema serialized correctly and the stub returned a conforming response on the first attempt.

What the run revealed

While analyzing the s export against the run output, s.unknown stood out as the only s.* helper without an @example in its JSDoc block:

Helper	Has @example?
s.array	✅
s.object	✅
s.record	✅
s.enum	✅
s.optional	✅
s.unknown	❌ (before this PR)

The header comment at the top of rig.ts also described s.unknown() with parentheses, implying it must always be called as a function — inconsistent with the "call as value or fn(desc)" pattern documented for the primitive helpers (s.string, s.number, etc.).

Change

• Added @example to s.unknown showing both bare (s.unknown) and description-form (s.unknown("raw API payload")) usage, matching the documentation style of every other s.* helper.
• Fixed the header comment entry from s.unknown() unconstrained JSON → s.unknown unconstrained JSON; call as value or s.unknown("description").

Verification

All 128 existing unit tests pass unchanged. No behavior is modified — this is a pure documentation improvement.

Generated by Daily Rig Sampler · 61.6 AIC · ⌖ 7.97 AIC · ⊞ 5.2K · ◷

[github-actions]

🧠 Matt Pocock Skills Reviewer has completed the skills-based review. ✅

[github-actions]

Skills-Based Review 🧠

Applied /grill-with-docs — approving; changes are consistent with the project's existing vocabulary and documentation patterns.

📋 Key Themes & Highlights

Key Themes

• Vocabulary consistency: The fix aligns s.unknown with the "call as value or fn(desc)" pattern already documented for all other primitive helpers (s.string, s.number, etc.)
• Documentation completeness: s.unknown was the only s.* helper missing an @example — this closes that gap

Positive Highlights

• ✅ @example block matches the style of every other s.* helper
• ✅ Header comment correction is precise and uses the domain's own wording
• ✅ No logic changes; all 128 tests pass unchanged

🧠 Reviewed using Matt Pocock's skills by Matt Pocock Skills Reviewer · 20 AIC · ⌖ 4.85 AIC · ⊞ 6.3K
_{Comment /matt to run again}