fix(running-example): consistent lab-script paths, tasks.json policy, no command collisions

- Lab-script path convention: course scripts live in modules/NN/lab/; copy the
  one a step needs into tasks-app, then run by bare name (M4/M6/M7/M26 + headers).
- tasks.json stays gitignored: M20 verifies via `cli.py list`/`cat tasks.json`
  (not git diff) and frames runtime state as deliberately ignored; M22 cleanup
  uses `rm tasks.json`; M10 review-lab gets its own .gitignore.
  Module 21's lab deliberately ships NO .gitignore (teaching device) — untouched.
- Stop running-example command collisions: M5 clear->search, M6 count/clear->
  stats/purge, M7 clear/count->wipe/remaining (README + scripts + agent prompts +
  branch/worktree names). M6 conflict still reproduces on the carried usage line.

Closes #7
Closes #10
Closes #11

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01TfzV5QvtPDz8LJS3Pu5VLT

modules/10-reviewing-code-you-didnt-write/README.md

@@ -206,6 +206,7 @@ real change, then review a diff the "AI" produced and catch the trap planted in
    ```bash
    mkdir -p ~/workflow-course/review-lab && cd ~/workflow-course/review-lab
    cp /path/to/modules/10-reviewing-code-you-didnt-write/lab/tasks-app/*.py .
+   printf 'tasks.json\n__pycache__/\n' > .gitignore   # keep generated runtime state out of your review diffs (Module 2)
    git init -qb main && git add . && git commit -qm "base: tasks-app"   # -b main so the git switch main / git diff main.. steps below resolve
 
    python cli.py add "write the review module"