feat(cookie): Pro-Cookie-Library-Abgleich (2287er OCD + 35er rich) + Panel

- analyze_cookies gleicht Cookies gegen BEIDE Libraries ab: compliance.cookie_library
  (2287, OCD/CC0 — Kategorie/Retention) + 35er rich-DB (technical_necessity/reid/
  schrems/eu_alternative). 5 Befund-Typen: tracker_as_necessary, missing_purpose,
  excessive_lifetime (Art.5), third_country (Art.44), eu_alternative (kommerziell).
- Endpoint GET /snapshots/{id}/cookie-check (load_big_library batch + analyze).
- Frontend CookieLibraryPanel im Snapshot-Detail.
- Fix CookieResultView: Zweck nicht mehr auf 60 Zeichen gekuerzt; Rolle 'unknown'
  als Strich statt 'Unbekannt'.

Tests: 7 backend + frontend vitest gruen.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

backend-compliance/compliance/api/agent_compliance_check_routes.py

@@ -223,6 +223,29 @@ async def get_snapshot(snapshot_id: str):
         db.close()
 
 
+@router.get("/snapshots/{snapshot_id}/cookie-check")
+async def snapshot_cookie_check(snapshot_id: str):
+    """Pro-Cookie-Abgleich der Snapshot-Vendors gegen cookie_knowledge_db."""
+    from fastapi import HTTPException
+    from database import SessionLocal
+    from compliance.services.check_snapshot import load_snapshot
+    from compliance.services.cookie_library_check import (
+        analyze_cookies, load_big_library,
+    )
+    db = SessionLocal()
+    try:
+        snap = load_snapshot(db, snapshot_id)
+        if not snap:
+            raise HTTPException(status_code=404, detail="snapshot not found")
+        vendors = snap.get("cmp_vendors") or []
+        names = [c.get("name", "")
+                 for v in vendors for c in (v.get("cookies") or [])]
+        big = load_big_library(db, names)
+        return analyze_cookies(vendors, big)
+    finally:
+        db.close()
+
+
 @router.get("/admin/benchmark")
 async def benchmark(
     industry: str = "",