Restructure: Move 52 files into 7 domain packages

korrektur/ zeugnis/ admin/ compliance/ worksheet/ training/ metrics/
52 shims, relative imports, RAG untouched.

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

klausur-service/backend/zeugnis/crawler.py

@@ -0,0 +1,26 @@
+"""
+Zeugnis Rights-Aware Crawler
+
+Barrel re-export: all public symbols for backward compatibility.
+"""
+
+from .text import (  # noqa: F401
+    extract_text_from_pdf,
+    extract_text_from_html,
+    chunk_text,
+    compute_hash,
+)
+from .storage import (  # noqa: F401
+    generate_embeddings,
+    upload_to_minio,
+    index_in_qdrant,
+)
+from .worker import (  # noqa: F401
+    CrawlerState,
+    ZeugnisCrawler,
+)
+from .control import (  # noqa: F401
+    start_crawler,
+    stop_crawler,
+    get_crawler_status,
+)