Add Ansicht step (Step 12) — read-only page layout preview

New pipeline step showing the reconstructed page with all zones
positioned at their original coordinates:
- Content zones with vocabulary grid cells
- Box zones with colored borders (from structure detection)
- Colspan cells rendered across multiple columns
- Multi-line cells (bullets) with pre-wrap whitespace
- Toggle to overlay original scan image at 15% opacity
- Proportionally scaled to viewport width
- Pure CSS positioning (no canvas/Fabric.js)

Pipeline: 14 steps (0-13), Ground Truth moved to Step 13.
Added colspan field to GridEditorCell type.

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

admin-lehrer/app/(admin)/ai/ocr-kombi/page.tsx

@@ -17,6 +17,7 @@ import { StepGridBuild } from '@/components/ocr-kombi/StepGridBuild'
 import { StepGridReview } from '@/components/ocr-kombi/StepGridReview'
 import { StepGutterRepair } from '@/components/ocr-kombi/StepGutterRepair'
 import { StepBoxGridReview } from '@/components/ocr-kombi/StepBoxGridReview'
+import { StepAnsicht } from '@/components/ocr-kombi/StepAnsicht'
 import { StepGroundTruth } from '@/components/ocr-kombi/StepGroundTruth'
 import { useKombiPipeline } from './useKombiPipeline'
 
@@ -100,6 +101,8 @@ function OcrKombiContent() {
       case 11:
         return <StepBoxGridReview sessionId={sessionId} onNext={handleNext} />
       case 12:
+        return <StepAnsicht sessionId={sessionId} onNext={handleNext} />
+      case 13:
         return (
           <StepGroundTruth
             sessionId={sessionId}

admin-lehrer/app/(admin)/ai/ocr-kombi/types.ts

@@ -41,6 +41,7 @@ export const KOMBI_V2_STEPS: PipelineStep[] = [
   { id: 'grid-review',   name: 'Grid-Review',        icon: '📊', status: 'pending' },
   { id: 'gutter-repair', name: 'Wortkorrektur',      icon: '🩹', status: 'pending' },
   { id: 'box-review',    name: 'Box-Review',          icon: '📦', status: 'pending' },
+  { id: 'ansicht',       name: 'Ansicht',             icon: '👁️', status: 'pending' },
   { id: 'ground-truth',  name: 'Ground Truth',       icon: '✅', status: 'pending' },
 ]
 
@@ -58,7 +59,8 @@ export const KOMBI_V2_UI_TO_DB: Record<number, number> = {
   9: 11,  // grid-review
   10: 11, // gutter-repair (shares DB step with grid-review)
   11: 11, // box-review (shares DB step with grid-review)
-  12: 12, // ground-truth
+  12: 11, // ansicht (shares DB step with grid-review)
+  13: 12, // ground-truth
 }
 
 /** Map from DB step to Kombi V2 UI step index */
@@ -72,7 +74,7 @@ export function dbStepToKombiV2Ui(dbStep: number): number {
   if (dbStep === 9) return 7  // structure
   if (dbStep === 10) return 8 // grid-build
   if (dbStep === 11) return 9 // grid-review
-  return 12                   // ground-truth
+  return 13                   // ground-truth
 }
 
 /** Document group: groups multiple sessions from a multi-page upload */