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/07-worktrees-running-agents-in-parallel/lab/agent-a-prompt.md

@@ -1,15 +1,15 @@
-# Agent A prompt — the `clear` command
+# Agent A prompt — the `wipe` command
 
-Paste this into the AI session you've pointed at the `tasks-app-clear` worktree folder.
+Paste this into the AI session you've pointed at the `tasks-app-wipe` worktree folder.
 
 ---
 
-Add a `clear` command to this task app that removes **all** tasks.
+Add a `wipe` command to this task app that removes **all** tasks.
 
-- Put the deletion logic on `TaskList` in `tasks.py` (a `clear()` method that empties the list),
-  and wire a `clear` command into the dispatch in `cli.py` that calls it and saves.
-- Running `python cli.py clear` should empty the list and print a short confirmation like
-  `cleared all tasks`.
-- After `clear`, `python cli.py list` should print `(no tasks yet)`.
+- Put the deletion logic on `TaskList` in `tasks.py` (a `wipe()` method that empties the list),
+  and wire a `wipe` command into the dispatch in `cli.py` that calls it and saves.
+- Running `python cli.py wipe` should empty the list and print a short confirmation like
+  `wiped all tasks`.
+- After `wipe`, `python cli.py list` should print `(no tasks yet)`.
 
 Make the change, then stop — I'll review the diff and commit it myself.

modules/07-worktrees-running-agents-in-parallel/lab/agent-b-prompt.md

@@ -1,14 +1,14 @@
-# Agent B prompt — the `count` command
+# Agent B prompt — the `remaining` command
 
-Paste this into the AI session you've pointed at the `tasks-app-count` worktree folder.
+Paste this into the AI session you've pointed at the `tasks-app-remaining` worktree folder.
 
 ---
 
-Add a `count` command to this task app that prints how many tasks are still pending.
+Add a `remaining` command to this task app that prints how many tasks are still pending.
 
 - Reuse the existing `pending()` method on `TaskList` in `tasks.py`; don't reimplement it.
-- Wire a `count` command into the dispatch in `cli.py`.
-- Running `python cli.py count` should print something like `2 pending` (the number of tasks not
+- Wire a `remaining` command into the dispatch in `cli.py`.
+- Running `python cli.py remaining` should print something like `2 pending` (the number of tasks not
   marked done).
 
 Make the change, then stop — I'll review the diff and commit it myself.

modules/07-worktrees-running-agents-in-parallel/lab/cleanup-worktrees.sh

@@ -1,23 +1,24 @@
 #!/usr/bin/env bash
 #
 # Module 7 lab — tear down the two worktrees created by setup-worktrees.sh.
-# Run from INSIDE your tasks-app repo:
+# Copy this into your tasks-app repo, then run it from inside:
 #
-#     bash modules/07-worktrees-running-agents-in-parallel/lab/cleanup-worktrees.sh
+#     cp /path/to/modules/07-worktrees-running-agents-in-parallel/lab/cleanup-worktrees.sh .
+#     bash cleanup-worktrees.sh
 #
 # `git worktree remove` deletes the folder AND clears Git's record of it; `prune` mops up any
 # worktrees whose folders were deleted by hand (which leaves a stale record otherwise).
 #
 # NOTE: --force discards UNCOMMITTED work in a worktree. Commit (or merge) before cleaning up.
-# This script assumes you already merged feature/clear and feature/count back into main.
+# This script assumes you already merged feature/wipe and feature/remaining back into main.
 #
 set -euo pipefail
 
 ROOT="$(git rev-parse --show-toplevel)"
 PARENT="$(cd "$ROOT/.." && pwd)"
 
-git worktree remove "$PARENT/tasks-app-clear" --force 2>/dev/null || true
-git worktree remove "$PARENT/tasks-app-count" --force 2>/dev/null || true
+git worktree remove "$PARENT/tasks-app-wipe" --force 2>/dev/null || true
+git worktree remove "$PARENT/tasks-app-remaining" --force 2>/dev/null || true
 git worktree prune
 
 echo
@@ -26,4 +27,4 @@ git worktree list
 
 echo
 echo "If you merged both branches you can also delete them:"
-echo "    git branch -d feature/clear feature/count"
+echo "    git branch -d feature/wipe feature/remaining"

modules/07-worktrees-running-agents-in-parallel/lab/setup-worktrees.sh

@@ -1,15 +1,16 @@
 #!/usr/bin/env bash
 #
 # Module 7 lab — create two linked worktrees off the tasks-app repo, each on its own branch.
-# Run this from INSIDE your tasks-app repo (the one you git-init'd in Module 2):
+# Copy this into your tasks-app repo (the one you git-init'd in Module 2), then run it from inside:
 #
-#     bash modules/07-worktrees-running-agents-in-parallel/lab/setup-worktrees.sh
+#     cp /path/to/modules/07-worktrees-running-agents-in-parallel/lab/setup-worktrees.sh .
+#     bash setup-worktrees.sh
 #
 # It places the new worktree folders next to the repo, so you end up with:
 #
-#     <parent>/tasks-app          (your existing repo, on its current branch)
-#     <parent>/tasks-app-clear    (new worktree on branch feature/clear)
-#     <parent>/tasks-app-count    (new worktree on branch feature/count)
+#     <parent>/tasks-app              (your existing repo, on its current branch)
+#     <parent>/tasks-app-wipe         (new worktree on branch feature/wipe)
+#     <parent>/tasks-app-remaining    (new worktree on branch feature/remaining)
 #
 set -euo pipefail
 
@@ -17,8 +18,8 @@ set -euo pipefail
 ROOT="$(git rev-parse --show-toplevel)"
 PARENT="$(cd "$ROOT/.." && pwd)"
 
-git worktree add "$PARENT/tasks-app-clear" -b feature/clear
-git worktree add "$PARENT/tasks-app-count" -b feature/count
+git worktree add "$PARENT/tasks-app-wipe" -b feature/wipe
+git worktree add "$PARENT/tasks-app-remaining" -b feature/remaining
 
 echo
 echo "Worktrees created. One repo, three checked-out branches:"