style(no-slop): de-em-dash the internal docs + config (repo now fully clean)

- AGENTS.md (the standard-bearer), _TEMPLATE.md, handoff.md, tools/README.md:
  em-dashes removed by restructuring, banned words replaced; all policy/structure
  and decisions preserved.
- .gitea/.github sync-wiki workflows, .claude/gitea-ship.json, .gitignore: em-dashes
  in comments/log strings/notes removed; YAML/JSON still valid.

The entire tracked repo is now em-dash-free (the lone remaining `—` is inside a
regex character class in tools/build_wiki.py, intentional, matches old titles).

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

.gitea/workflows/sync-wiki.yml

@@ -1,8 +1,8 @@
 # Render the course (single source of truth = modules/) into the Gitea wiki on
-# every push to main. The wiki is generated BUILD OUTPUT — never hand-edit it.
+# every push to main. The wiki is generated BUILD OUTPUT; never hand-edit it.
 #
 # Runs on the stack's shared `docker` runners (Linux). To actually push the wiki it
-# needs a repo secret WIKI_TOKEN with wiki write (a scoped PAT/deploy token — NOT a
+# needs a repo secret WIKI_TOKEN with wiki write (a scoped PAT/deploy token, NOT a
 # site-admin token). Until that secret exists the job skips cleanly (stays green).
 name: Sync course wiki
 on:
@@ -27,9 +27,9 @@ jobs:
           WIKI_TOKEN: ${{ secrets.WIKI_TOKEN }}
         run: |
           set -euo pipefail
-          echo "runner: $(uname -srm) — $(python3 --version 2>/dev/null || echo 'python3 missing')"
+          echo "runner: $(uname -srm); $(python3 --version 2>/dev/null || echo 'python3 missing')"
           if [ -z "${WIKI_TOKEN:-}" ]; then
-            echo "::warning::WIKI_TOKEN secret not set — skipping wiki sync. Add the secret to enable auto-sync."
+            echo "::warning::WIKI_TOKEN secret not set; skipping wiki sync. Add the secret to enable auto-sync."
             exit 0
           fi
           command -v python3 >/dev/null || { apt-get update && apt-get install -y --no-install-recommends python3; }