✨ feat(playbook): add syntax book and codex skills tooling

codex/skills/systematic-debugging/SKILL.md

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+---
+name: systematic-debugging
+description: Systematic debugging for bugs, failing tests, regressions (TSL/C++/Python). Triggers: debug, failing test, regression, crash, 复现, 定位, 排查, 调试.
+---
+
+# Systematic Debugging（系统化调试）
+
+## When to Use
+- Bugs, crashes, failing/flaky tests, regressions
+- “It doesn’t work” reports with unclear reproduction
+
+## Inputs（required）
+- Expected vs actual behavior
+- Repro command/steps (or best-known approximation)
+- Logs/traces/screenshots/error output
+- Environment details (OS, versions, configs)
+
+## Procedure（default）
+1. **Reproduce**
+   - Make the failure deterministic if possible
+   - Minimize repro steps (smallest input/command)
+
+2. **Localize**
+   - Identify failing component and boundary conditions
+   - Add temporary logging/assertions if needed (then remove)
+
+3. **Hypothesize & Test**
+   - Form a small number of hypotheses
+   - Design quick experiments to falsify each hypothesis
+
+4. **Fix & Verify**
+   - Fix the root cause (not just symptoms)
+   - Add/update tests; rerun the minimal relevant suite
+
+## Output Contract（stable）
+- Repro: exact steps/command
+- Diagnosis: root cause + evidence
+- Fix: what changed + why it works
+- Verification: commands + outputs/exit codes
+- Follow-ups: hardening or cleanup tasks
+
+## Guardrails
+- Avoid changing multiple variables at once
+- Prefer instrumentation and evidence over guessing
+- Keep fixes minimal and scoped
+