feat(audit): P107 Branchen-Benchmark-Cockpit fuer Big-4-Demos

benchmark_extractor.py — extract_kpis() liefert 18 KPIs pro Snapshot:
* vendors_total, vendors_us, vendors_non_eu (mit % je Vendor-Land)
* source_breakdown (llm/library/flat_pattern/table_paste/html_table_dom)
* max/avg cookies_per_vendor (Konzentrations-Mass)
* cookies_in_browser, cookies_detailed_count, cookie_doc_chars
* banner_detected, banner_provider, banner_violations
* compliance_score, data_quality_pct (wie viele unserer Datenquellen
  haben Inhalt)
* saving_low/high_eur (Heuristik: (vendors - 10) × 1k-5k)

anonymize_kpis() ersetzt site_label durch 'OEM 1/2/3' (Industry-Prefix
Map: automotive→OEM, banking→Bank, chemistry→Chem, luftfahrt→Airline).

GET /api/compliance/agent/admin/benchmark?industry=automotive&sites=
VW,BMW,Mercedes&anonymized=true — liefert kpis + summary
(n_sites, avg_vendors, total_saving_high).

Admin-Page /sdk/benchmark:
* Filter-Leiste: Industry-Dropdown, Sites-Input + 5 Preset-Gruppen
  (Automotive OEMs / Zulieferer, Chemie DAX, Luftfahrt, Banking DAX)
* Anonymize-Toggle prominent
* 5 Summary-KPI-Karten oben
* Vergleichstabelle 13 Spalten (Score, Vendors, US%, Drittland%,
  Cookies-Browser, Cookie-Doc-kB, Banner ✓/✗, Provider, Verstoesse,
  Saving €/Jahr, Daten-Qualitaet, Captured-Time)
* Red-/Amber-/Green-Indikatoren bei US%/Score/Drittland
* Big-4-Hinweis-Footer

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

backend-compliance/compliance/api/agent_compliance_check_routes.py

@@ -207,6 +207,42 @@ async def get_snapshot(snapshot_id: str):
         db.close()
 
 
+@router.get("/admin/benchmark")
+async def benchmark(
+    industry: str = "",
+    sites: str = "",
+    anonymized: bool = False,
+    limit: int = 50,
+):
+    """P107 — Branchen-Benchmark-Cockpit Endpoint.
+    industry: 'automotive' / 'banking' / etc (optional)
+    sites: comma-separated site_label list (optional)
+    anonymized: bool — wenn true, Hersteller-Namen → 'OEM 1/2/3'
+    """
+    from database import SessionLocal
+    from compliance.services.benchmark_extractor import (
+        load_snapshots_for_benchmark, anonymize_kpis,
+        build_benchmark_summary,
+    )
+    site_list = [s.strip() for s in sites.split(",") if s.strip()] if sites else None
+    db = SessionLocal()
+    try:
+        kpis = load_snapshots_for_benchmark(
+            db, industry=industry or None, sites=site_list, limit=limit,
+        )
+    finally:
+        db.close()
+    if anonymized:
+        kpis = anonymize_kpis(kpis, industry=industry)
+    return {
+        "industry":  industry or "all",
+        "anonymized": anonymized,
+        "sites":     [k.get("site_label") for k in kpis],
+        "kpis":      kpis,
+        "summary":   build_benchmark_summary(kpis),
+    }
+
+
 @router.post("/admin/tcf-ingest")
 async def tcf_ingest():
     """P105 — IAB TCF Vendor-Liste ingestieren / refreshen.