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/11-collaboration-humans-and-agents/lab/issue.md

@@ -1,8 +1,8 @@
 <!--
-  Module 11 lab — the issue to file (the "contract" / station 1 of the loop).
+  Module 11 lab: the issue to file (the "contract" / station 1 of the loop).
 
   Create a new issue on your git host. Paste the line below as the TITLE and everything under
-  "Body" as the issue description. Note the number the host assigns it (e.g. #42) — every later
+  "Body" as the issue description. Note the number the host assigns it (e.g. #42); every later
   step references it. Assign it to yourself for the first run-through.
 -->