style(no-slop): remove every em-dash + banned words across all modules + capstone

Apply the no-ai-slop standard (now binding in AGENTS.md): the em-dash character is
banned outright (restructured, not blind-replaced), plus the banned word/phrase
list (delve, leverage, robust, seamless, truly, unlock, etc.). 0 em-dashes remain
in modules + capstone; the only "robust" left is the planted M10 ai-change.patch
trap. Module H1 titles use a colon separator.

All deliberate teaching devices preserved; labs compile/parse (py/sh/yaml/json);
no junk. AGENTS.md updated with the hard no-slop rules.

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

modules/21-skills-teaching-the-ai-your-playbook/lab/add-command-skill.md

@@ -1,14 +1,14 @@
 # Skill: Add a new tasks-app command, end to end
 
 > A reusable playbook. Don't paste this whole file into a chat and hope. Point your agentic tool at
-> it by name — "follow `add-command.md` to add a `clear` command" — or drop it wherever your tool
+> it by name ("follow `add-command.md` to add a `clear` command"), or drop it wherever your tool
 > auto-discovers procedures (a skills/commands folder). The steps are the same either way.
 
 ## When to use this
 
 Invoke this whenever the task is **"add a new subcommand to the `tasks-app` CLI."** It exists so a
 new command lands the *same* way every time: real code, a real test, a changelog line, and a clean
-commit — never just the code with the rest forgotten.
+commit; never just the code with the rest forgotten.
 
 If the task is *not* "add a CLI command" (a bug fix, a refactor, a docs change), this skill does not
 apply. Don't force it.
@@ -17,18 +17,18 @@ apply. Don't force it.
 
 Ask for these if they weren't given:
 
-- `COMMAND_NAME` — the subcommand word, e.g. `clear`.
-- `WHAT_IT_DOES` — one sentence of intended behavior, e.g. "remove all tasks."
+- `COMMAND_NAME`: the subcommand word, e.g. `clear`.
+- `WHAT_IT_DOES`: one sentence of intended behavior, e.g. "remove all tasks."
 
 ## Project facts (so you don't have to rediscover them)
 
 - Core logic lives in `tasks.py` (the `TaskList` class). The CLI front end is `cli.py`. State
-  persists to `tasks.json` — **never edit `tasks.json` by hand; it's generated.**
-- Tests live in `test_tasks.py` and run with `python -m unittest`. Standard library only — no
+  persists to `tasks.json`. **Never edit `tasks.json` by hand; it's generated.**
+- Tests live in `test_tasks.py` and run with `python -m unittest`. Standard library only; no
   third-party packages, no new dependencies.
 - The human-facing change log is `CHANGELOG.md`, newest entry on top.
 
-## Procedure — do these in order, do not skip
+## Procedure: do these in order, do not skip
 
 1. **Core logic in `tasks.py`.** If the command needs new behavior on the task list, add a small
    method to `TaskList` (e.g. `clear()`). Keep it minimal; match the existing style. If the command
@@ -43,7 +43,7 @@ Ask for these if they weren't given:
    A test that passes against a broken implementation is worse than no test.
 
 4. **Run the tests.** `python -m unittest` from the project root. Do not claim success until it's
-   green. If it fails, fix the code — not the test — and run again.
+   green. If it fails, fix the code, not the test, and run again.
 
 5. **Smoke-test the CLI.** Actually run it: `python cli.py COMMAND_NAME`, then `python cli.py list`
    to confirm the visible result. Paste what you ran and what it printed.
@@ -60,8 +60,8 @@ Ask for these if they weren't given:
 - `python -m unittest` is green and includes a new test that actually exercises `COMMAND_NAME`.
 - `python cli.py COMMAND_NAME` does `WHAT_IT_DOES` and you've shown the output.
 - `CHANGELOG.md` has a new top line for the command.
-- One commit contains the code, the test, and the changelog line — and nothing else (no
+- One commit contains the code, the test, and the changelog line, and nothing else (no
   `tasks.json`, no unrelated reformatting).
 
-If any of those is missing, the skill isn't finished. Report which step failed and stop — don't
+If any of those is missing, the skill isn't finished. Report which step failed and stop; don't
 paper over it.

modules/21-skills-teaching-the-ai-your-playbook/lab/tasks-app/cli.py

@@ -5,7 +5,7 @@ Run it:
     python cli.py list
     python cli.py count
 
-State is kept in tasks.json next to this file. The same minimal app from Module 1 onward — the
+State is kept in tasks.json next to this file. The same minimal app from Module 1 onward; the
 target your "add a command" skill extends.
 """