fix(quality): Ruff/CVE/TS-Fixes, 104 neue Tests, Complexity-Refactoring

- Ruff: 144 auto-fixes (unused imports, == None → is None), F821/F811/F841 manuell
- CVEs: python-multipart>=0.0.22, weasyprint>=68.0, pillow>=12.1.1, npm audit fix (0 vulns)
- TS: 5 tote Drafting-Engine-Dateien entfernt, allowed-facts/sanitizer/StepHeader/context fixes
- Tests: +104 (ISMS 58, Evidence 18, VVT 14, Generation 14) → 1449 passed
- Refactoring: collect_ci_evidence (F→A), row_to_response (E→A), extract_requirements (E→A)
- Dead Code: pca-platform, 7 Go-Handler, dsr_api.py, duplicate Schemas entfernt

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

backend-compliance/compliance/tests/test_auto_risk_updater.py

@@ -4,10 +4,8 @@ Tests for the AutoRiskUpdater Service.
 Sprint 6: CI/CD Evidence Collection & Automatic Risk Updates (2026-01-18)
 """
 
-import pytest
 from datetime import datetime
-from unittest.mock import MagicMock, patch
-from uuid import uuid4
+from unittest.mock import MagicMock
 
 from ..services.auto_risk_updater import (
     AutoRiskUpdater,
@@ -18,9 +16,7 @@ from ..services.auto_risk_updater import (
     CONTROL_SCAN_MAPPING,
 )
 from ..db.models import (
-    ControlDB, ControlStatusEnum,
-    EvidenceDB, EvidenceStatusEnum,
-    RiskDB, RiskLevelEnum,
+    ControlStatusEnum,
 )