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

@@ -1,6 +1,6 @@
 #!/usr/bin/env bash
 #
-# Module 7 lab — tear down the two worktrees created by setup-worktrees.sh.
+# Module 7 lab: tear down the two worktrees created by setup-worktrees.sh.
 # The tool the coordinating AI session runs to clean up. Hand it to your agent, or copy it into
 # tasks-app and let the agent run it:
 #