fix: PLZ regex matches lowercase text and D-78467 format

Patterns ran on text.lower() but searched [A-Z] — changed to [a-z].
Also accept D-12345 prefix (common German format).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

backend-compliance/compliance/services/doc_checks/dse_checks.py

@@ -25,8 +25,8 @@ ART13_CHECKLIST = [
         "label": "Vollstaendige Anschrift (PLZ + Ort)",
         "level": 2, "parent": "controller",
         "patterns": [
-            r"\d{5}\s+[A-Z\u00c0-\u017e]\w+",
-            r"[A-Z\u00c0-\u017e]\w+(?:str|stra(?:ss|ß)e|weg|platz|allee|gasse)\s*\.?\s*\d",
+            r"(?:d[\-\s]?)?\d{5}\s+[a-z\u00c0-\u017e]\w{2,}",
+            r"[a-z\u00c0-\u017e]\w+(?:str|stra(?:ss|ß)e|weg|platz|allee|gasse|ring|damm)\s*\.?\s*\d",
         ],
         "severity": "MEDIUM",
     },