Fix: Update all old-style imports inside packages to new paths

65 files in klausur-service packages + 3 in backend-lehrer packages
had stale imports referencing deleted shim modules.

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

klausur-service/backend/vocab/worksheet/compare_api.py

@@ -23,7 +23,7 @@ from .generation import convert_pdf_page_to_image
 
 # Try to import Tesseract extractor
 try:
-    from tesseract_vocab_extractor import (
+    from ocr.engines.tesseract_extractor import (
         run_tesseract_pipeline,
         match_positions_to_vocab, TESSERACT_AVAILABLE,
     )
@@ -32,7 +32,7 @@ except ImportError:
 
 # Try to import CV Pipeline
 try:
-    from cv_vocab_pipeline import run_cv_pipeline, CV_PIPELINE_AVAILABLE
+    from ocr.cv_pipeline import run_cv_pipeline, CV_PIPELINE_AVAILABLE
 except ImportError:
     CV_PIPELINE_AVAILABLE = False
 
@@ -328,7 +328,7 @@ async def analyze_grid(session_id: str, page_number: int, use_tesseract: bool =
             # Run Tesseract if not already cached
             if not tess_page_data:
                 logger.info("Running Tesseract for grid analysis (not cached)")
-                from tesseract_vocab_extractor import run_tesseract_pipeline as _run_tess
+                from ocr.engines.tesseract_extractor import run_tesseract_pipeline as _run_tess
                 tess_page_data = await _run_tess(image_data, lang="eng+deu")
                 session[f"tesseract_page_{page_number}"] = tess_page_data
                 session["tesseract_words"] = tess_page_data.get("words", [])