Fix #158: Update LLM guide map example to use fn destructuring syntax

[andreasronge]

Summary

Updates the map iteration example in docs/ptc-lisp-llm-guide.md to demonstrate the new vector destructuring syntax instead of the old first/last workaround pattern.

This completes the documentation updates for Epic #147 (Function Parameter Destructuring).

Changes

• Line 263: Updated map example from (map (fn [entry] {:cat (first entry) :avg (avg-by :amount (last entry))}) grouped) to (map (fn [[key value]] {:cat key :avg (avg-by :amount value)}) grouped)

This demonstrates the idiomatic destructuring pattern that is now available and preferred over the verbose workaround.

Fixes #158

[github-actions]

PR Review: Fix #158: Update LLM guide map example to use fn destructuring syntax

Summary

Minimal documentation update that changes a single example in the LLM guide from the old first/last workaround pattern to the idiomatic vector destructuring syntax. Clean and well-scoped change.

What's Good

• Correctly targeted: Updates exactly the line specified in issue Update LLM guide map example to use fn destructuring syntax #158 (line 263)
• Pattern matches spec: The new syntax (fn [[key value]] ...) matches Section 5.1 of the fn-destructuring spec (lines 397-400)
• Quality verified: All 954 tests pass, format check passes, compilation clean
• Appropriate scope: This completes the final documentation task for Epic Epic: Function Parameter Destructuring #147

Issues (Must Fix)

None.

Suggestions (Optional)

None - the change is minimal and correctly scoped.

Security

No concerns - documentation-only change.

Documentation

• ✅ The LLM guide example now demonstrates the preferred idiomatic pattern
• ✅ Spec document (ptc-lisp-fn-destructuring-spec.md) correctly retains the old pattern as "before" context in Section 1.2 - this is intentional and should not be changed
• ✅ Special Forms section (lines 213-215) already shows destructuring syntax from prior work
• ✅ Common Mistakes table doesn't have the old workaround entry (either removed in prior PR or never added)

Verification

• Issue Update LLM guide map example to use fn destructuring syntax #158 requirements: ✅ Met
• Spec Section 5.1 compliance: ✅ The example uses [key value] destructuring pattern as prescribed
• Dependencies (Extend analyze_pattern for vector patterns #150, Add evaluator unit tests for fn parameter destructuring patterns #156): ✅ Already closed per issue review
• Quality checks: ✅ All passing (954 tests, format, compilation)

Verdict

Approve - This is a well-scoped, correctly implemented documentation update that completes Epic #147.

[andreasronge]

Auto-Triage Summary

Review Analysis

The automated review found zero issues requiring action. This PR is a clean, minimal documentation update that:

• Updates exactly the line specified in issue Update LLM guide map example to use fn destructuring syntax #158 (line 263 of LLM guide)
• Correctly applies the fn [[key value]] destructuring pattern per spec Section 5.1
• Passes all quality checks (954 tests, format, compilation)
• Appropriately scoped as a documentation-only change

Decisions Made

#	Issue	Decision	Action
-	No issues found	-	-

Status

• FIX_NOW items: 0
• Issues created: 0
• Items ignored: 0

✅ Ready to merge - All review criteria met, no action items required.