[split-required] Split 58 monoliths across Python, Go, TypeScript (Phases 1-3)

Phase 1 — Python (klausur-service): 5 monoliths → 36 files
- dsfa_corpus_ingestion.py (1,828 LOC → 5 files)
- cv_ocr_engines.py (2,102 LOC → 7 files)
- cv_layout.py (3,653 LOC → 10 files)
- vocab_worksheet_api.py (2,783 LOC → 8 files)
- grid_build_core.py (1,958 LOC → 6 files)

Phase 2 — Go (edu-search-service, school-service): 8 monoliths → 19 files
- staff_crawler.go (1,402 → 4), policy/store.go (1,168 → 3)
- policy_handlers.go (700 → 2), repository.go (684 → 2)
- search.go (592 → 2), ai_extraction_handlers.go (554 → 2)
- seed_data.go (591 → 2), grade_service.go (646 → 2)

Phase 3 — TypeScript (admin-lehrer): 45 monoliths → 220+ files
- sdk/types.ts (2,108 → 16 domain files)
- ai/rag/page.tsx (2,686 → 14 files)
- 22 page.tsx files split into _components/ + _hooks/
- 11 component files split into sub-components
- 10 SDK data catalogs added to loc-exceptions
- Deleted dead backup index_original.ts (4,899 LOC)

All original public APIs preserved via re-export facades.
Zero new errors: Python imports verified, Go builds clean,
TypeScript tsc --noEmit shows only pre-existing errors.

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

admin-lehrer/components/ocr/GTImageCrop.tsx

@@ -0,0 +1,52 @@
+/**
+ * GTImageCrop — Renders a cropped region of an image based on a bounding box.
+ *
+ * Used in the Ground Truth labeling UI to show row and column crops
+ * of the current entry being reviewed.
+ */
+
+import type { BBox } from './ground-truth-types'
+
+interface GTImageCropProps {
+  imageUrl: string
+  bbox: BBox
+  naturalWidth: number
+  naturalHeight: number
+  maxWidth?: number
+  label?: string
+}
+
+export function GTImageCrop({ imageUrl, bbox, naturalWidth, naturalHeight, maxWidth = 380, label }: GTImageCropProps) {
+  if (!bbox || bbox.w === 0 || bbox.h === 0) return null
+
+  const cropWPx = (bbox.w / 100) * naturalWidth
+  const cropHPx = (bbox.h / 100) * naturalHeight
+  if (cropWPx < 1 || cropHPx < 1) return null
+
+  const scale = maxWidth / cropWPx
+  const displayH = cropHPx * scale
+
+  return (
+    <div>
+      {label && <div className="text-xs font-medium text-slate-500 mb-1">{label}</div>}
+      <div
+        className="rounded-lg border border-slate-200 overflow-hidden bg-white"
+        style={{ width: maxWidth, height: Math.min(displayH, 120), overflow: 'hidden', position: 'relative' }}
+      >
+        <img
+          src={imageUrl}
+          alt=""
+          draggable={false}
+          style={{
+            position: 'absolute',
+            width: naturalWidth * scale,
+            height: naturalHeight * scale,
+            left: -(bbox.x / 100) * naturalWidth * scale,
+            top: -(bbox.y / 100) * naturalHeight * scale,
+            maxWidth: 'none',
+          }}
+        />
+      </div>
+    </div>
+  )
+}