feat: slice 5 - components declared, group checks live, mirror dry-run

Gate 4, slice 5: eight component declarations under docs/components/
(filename = canonical slug, F-008 answered by construction; staged
dormancy of thread-net-git/threadnet-operating finally representable,
game-operating/gameserver as external with their field-test caveats),
five pointer-rollout follow-up issues (0035-0039, ADR-0013),
gruppenpruefung.py joins the stillstandspruefung family (runtime group
list vs declarations, pointer presence, group-wide milestone/priority
duty, issue drift, git hygiene since the 2026-08-07 rule boundary,
bot exception per ADR-0009) with its own scheduled CI job, and
spiegel_issues.py mirrors repo to GitLab (title, state, milestone,
priority, due, status label only - never descriptions, never
backwards, dry-run by default, GitLab-only issues are reported and
never auto-closed).

Verified - all four pattern demos fire (acceptance criterion 5, 4/4):
A) old CLAUDE.md claims M1-M4 while the frozen export knows M5;
B) hygiene over full clone history finds 222 real-clock commits by
own identities (matches the frozen Session-1 numbers per repo);
C) covered in slices 3/4 (five task blocks, now 0);
D) covered in slice 3 (orphaned SHA citations, now resolved/curated).
Live run (read-only): exactly the four missing pointers (F-011) and
gitops#61 without milestone as red findings, zero drift on all 26
mirrored issues, group list consistent. Mirror dry-run plans 7
creations, 0 updates, wrote nothing. Offline chain green: validate
0/0, gen_status --check current, drift 0, prosa 0.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

.gitlab-ci.yml

@@ -50,3 +50,22 @@ validate:
     - python3 scripts/pruefe_upstream_drift.py
     - python3 scripts/pruefe_prosa.py
   allow_failure: false
+
+# Verbund-Prüfung (ADR-0012/0013): Gruppenliste vs. docs/components/,
+# Pointer-Praesenz, Meilenstein-/Prioritaetspflicht, Issue-Drift,
+# Git-Hygiene. Gleiche Regeln wie die Stillstandspruefung: geplant/von
+# Hand, rot = Alarm, Abbruch ohne Token.
+gruppenpruefung:
+  stage: pruefen
+  image: python:3.12-alpine
+  rules:
+    - if: $CI_PIPELINE_SOURCE == "schedule"
+    - if: $CI_PIPELINE_SOURCE == "web"
+  script:
+    - |
+      if [ -z "$GITLAB_TOKEN" ]; then
+        echo "GITLAB_TOKEN fehlt (Gruppen-Token mit read_api)."
+        exit 1
+      fi
+    - python3 scripts/gruppenpruefung.py
+  allow_failure: false