docs: add Think With AI pivot plan

[nickmeinhold]

Summary

• Adds docs/pivot.plan — full implementation plan for pivoting the challenge system from teaching Dart syntax to teaching AI collaboration skills
• Adds reference to the plan in CLAUDE.md's Current Work section
• Five new challenge types (decompose, prompt craft, evaluate, iterate, compose) extending alongside existing code challenges

Test plan

• Verify docs/pivot.plan is readable and complete
• Verify CLAUDE.md reference links correctly
• No code changes — docs only

🤖 Generated with Claude Code

[kelvin-bit-brawler]

Code Review - PR #203

Summary: Adds a strategic pivot plan document and CLAUDE.md reference for shifting Tech World challenges from Dart syntax to AI collaboration skills.

Changes reviewed:

• docs/pivot.plan — New 138-line implementation plan covering pedagogical framework, data model changes, UI changes, bot evaluation changes, and phased rollout
• CLAUDE.md — 4-line addition referencing the plan under Current Work

Quality Assessment:

Aspect	Status	Notes
Code Quality	✅ pass	No code changes — docs only
Tests	✅ pass	N/A for documentation
Security	✅ pass	No runtime changes
Performance	✅ pass	No runtime changes

Observations:

• Plan is well-structured with clear phases, file-level specifics, and a verification section
• Backward compatibility is explicitly addressed (existing code challenges remain as ChallengeType.code)
• The "mirror challenges" concept (same problem as both code + prompt-craft) is a particularly strong pedagogical insight
• CLAUDE.md reference uses a relative link which will resolve correctly on GitHub

Verdict: APPROVE
Docs-only PR with a thorough, actionable plan. No code changes, no risk. Ship it.

[github-actions]

LCOV of commit 0f9cd43 during Test on PR #248

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