[split-required] Split 500-850 LOC files (batch 2)

backend-lehrer (10 files):
- game/database.py (785 → 5), correction_api.py (683 → 4)
- classroom_engine/antizipation.py (676 → 5)
- llm_gateway schools/edu_search already done in prior batch

klausur-service (12 files):
- orientation_crop_api.py (694 → 5), pdf_export.py (677 → 4)
- zeugnis_crawler.py (676 → 5), grid_editor_api.py (671 → 5)
- eh_templates.py (658 → 5), mail/api.py (651 → 5)
- qdrant_service.py (638 → 5), training_api.py (625 → 4)

website (6 pages):
- middleware (696 → 8), mail (733 → 6), consent (628 → 8)
- compliance/risks (622 → 5), export (502 → 5), brandbook (629 → 7)

studio-v2 (3 components):
- B2BMigrationWizard (848 → 3), CleanupPanel (765 → 2)
- dashboard-experimental (739 → 2)

admin-lehrer (4 files):
- uebersetzungen (769 → 4), manager (670 → 2)
- ChunkBrowserQA (675 → 6), dsfa/page (674 → 5)

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

klausur-service/backend/grid_editor_api_unified.py

@@ -0,0 +1,71 @@
+"""
+Grid Editor API — unified grid endpoints.
+"""
+
+import logging
+
+from fastapi import APIRouter, HTTPException
+
+from ocr_pipeline_session_store import (
+    get_session_db,
+    update_session_db,
+)
+
+logger = logging.getLogger(__name__)
+
+router = APIRouter(prefix="/api/v1/ocr-pipeline", tags=["grid-editor"])
+
+
+@router.post("/sessions/{session_id}/build-unified-grid")
+async def build_unified_grid_endpoint(session_id: str):
+    """Build a single-zone unified grid merging content + box zones.
+
+    Takes the existing multi-zone grid_editor_result and produces a
+    unified grid where boxes are integrated into the main row sequence.
+    Persists as unified_grid_result (preserves original multi-zone data).
+    """
+    session = await get_session_db(session_id)
+    if not session:
+        raise HTTPException(status_code=404, detail=f"Session {session_id} not found")
+
+    grid_data = session.get("grid_editor_result")
+    if not grid_data:
+        raise HTTPException(status_code=400, detail="No grid data. Run build-grid first.")
+
+    from unified_grid import build_unified_grid
+
+    result = build_unified_grid(
+        zones=grid_data.get("zones", []),
+        image_width=grid_data.get("image_width", 0),
+        image_height=grid_data.get("image_height", 0),
+        layout_metrics=grid_data.get("layout_metrics", {}),
+    )
+
+    # Persist as separate field (don't overwrite original multi-zone grid)
+    await update_session_db(session_id, unified_grid_result=result)
+
+    logger.info(
+        "build-unified-grid session %s: %d rows, %d cells",
+        session_id,
+        result.get("summary", {}).get("total_rows", 0),
+        result.get("summary", {}).get("total_cells", 0),
+    )
+
+    return result
+
+
+@router.get("/sessions/{session_id}/unified-grid")
+async def get_unified_grid(session_id: str):
+    """Retrieve the unified grid for a session."""
+    session = await get_session_db(session_id)
+    if not session:
+        raise HTTPException(status_code=404, detail=f"Session {session_id} not found")
+
+    result = session.get("unified_grid_result")
+    if not result:
+        raise HTTPException(
+            status_code=404,
+            detail="No unified grid. Run build-unified-grid first.",
+        )
+
+    return result