feat(audit): P75 Banner-vs-CMP + P84 Diff-Mode + P74/P96/P97 Doc-Types

P75 — check_banner_vs_cmp_partner_count: wenn Banner-Text 'N Partner'
nennt und N < cmp_vendors * 0.6, HIGH-Finding (Art. 13(1)(e) DSGVO).
Erkennt Verharmlosung der tatsaechlichen Vendor-Anzahl.

P84 — run_diff.py: vergleicht aktuellen Lauf mit letztem Snapshot
derselben Site (set-Diff auf normalisierten Finding-Labels). Block
ueber dem GF-1-Pager: 'Seit letztem Lauf: X Findings weg, Y neue'.
USP — keiner der grossen Anbieter hat das.

P74/P96/P97 — Labels fuer legal_notice (Rechtliche Hinweise / IP /
Forward-Looking), dsa (Art. 12+17 Digital Services Act), lizenzhinweise
(OSS-Compliance) in _DOC_TYPE_LABELS registriert. Echte Pflichtangaben-
Checks kommen separat.

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

backend-compliance/compliance/api/agent_compliance_check_routes.py

@@ -1091,7 +1091,7 @@ async def _run_compliance_check(check_id: str, req: ComplianceCheckRequest):
             cookie_doc_for_check = (doc_texts.get("cookie")
                                     or doc_texts.get("dse") or "")
             cons_findings = run_consistency_checks(
-                banner_result or {}, cookie_doc_for_check,
+                banner_result or {}, cookie_doc_for_check, cmp_vendors,
             )
             if cons_findings:
                 consistency_html = build_consistency_block_html(cons_findings)
@@ -1115,8 +1115,28 @@ async def _run_compliance_check(check_id: str, req: ComplianceCheckRequest):
         except Exception as e:
             logger.warning("P82 GF-1-pager skipped: %s", e)
 
+        # P84: Diff-Mode — "Seit letztem Lauf X Findings weg, Y neue".
+        diff_html = ""
+        try:
+            from database import SessionLocal as _SL
+            from compliance.services.run_diff import (
+                compute_diff, build_diff_block_html,
+            )
+            _diff_db = _SL()
+            try:
+                diff = compute_diff(
+                    _diff_db, check_id, domain_for_exec or "",
+                    banner_result, scorecard,
+                )
+                if diff:
+                    diff_html = build_diff_block_html(diff)
+            finally:
+                _diff_db.close()
+        except Exception as e:
+            logger.warning("P84 diff-mode skipped: %s", e)
+
         full_html = (
-            gf_one_pager_html
+            gf_one_pager_html + diff_html
             + critical_html + scope_disclaimer_html + exec_summary_html
             + cookie_arch_html + summary_html + scanned_html + profile_html
             + scorecard_html + redundancy_html
@@ -1895,6 +1915,12 @@ _DOC_TYPE_LABELS = {
     "social_media": "Social Media Datenschutz",
     "nutzungsbedingungen": "Nutzungsbedingungen",
     "dsb": "DSB-Kontakt",
+    # P74: Legal-Notice / Rechtliche Hinweise (IP, Forward-Looking, Risiko)
+    "legal_notice": "Rechtliche Hinweise",
+    # P96: Digital Services Act-Pflichtangaben (Art. 12+17 DSA)
+    "dsa": "DSA-Pflichtangaben",
+    # P97: Lizenzhinweise Dritter (OSS-Compliance)
+    "lizenzhinweise": "Lizenzhinweise Dritter",
 }
 
 # Canonical doc types in the same order as the frontend ComplianceCheckTab.