fix: Restore all files lost during destructive rebase

A previous `git pull --rebase origin main` dropped 177 local commits,
losing 3400+ files across admin-v2, backend, studio-v2, website,
klausur-service, and many other services. The partial restore attempt
(660295e2) only recovered some files.

This commit restores all missing files from pre-rebase ref 98933f5e
while preserving post-rebase additions (night-scheduler, night-mode UI,
NightModeWidget dashboard integration).

Restored features include:
- AI Module Sidebar (FAB), OCR Labeling, OCR Compare
- GPU Dashboard, RAG Pipeline, Magic Help
- Klausur-Korrektur (8 files), Abitur-Archiv (5+ files)
- Companion, Zeugnisse-Crawler, Screen Flow
- Full backend, studio-v2, website, klausur-service
- All compliance SDKs, agent-core, voice-service
- CI/CD configs, documentation, scripts

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

studio-v2/components/worksheet-editor/ExportPanel.tsx

@@ -0,0 +1,216 @@
+'use client'
+
+import { useState } from 'react'
+import { useTheme } from '@/lib/ThemeContext'
+import { useLanguage } from '@/lib/LanguageContext'
+import { useWorksheet } from '@/lib/worksheet-editor/WorksheetContext'
+
+interface ExportPanelProps {
+  isOpen: boolean
+  onClose: () => void
+}
+
+export function ExportPanel({ isOpen, onClose }: ExportPanelProps) {
+  const { isDark } = useTheme()
+  const { t } = useLanguage()
+  const { exportToPDF, exportToImage, document, saveDocument, isDirty } = useWorksheet()
+
+  const [isExporting, setIsExporting] = useState(false)
+  const [exportFormat, setExportFormat] = useState<'pdf' | 'png' | 'jpg'>('pdf')
+
+  const handleExport = async () => {
+    setIsExporting(true)
+
+    try {
+      let blob: Blob
+      let filename: string
+
+      if (exportFormat === 'pdf') {
+        blob = await exportToPDF()
+        filename = `${document?.title || 'Arbeitsblatt'}.pdf`
+      } else {
+        blob = await exportToImage(exportFormat)
+        filename = `${document?.title || 'Arbeitsblatt'}.${exportFormat}`
+      }
+
+      // Download file
+      const url = URL.createObjectURL(blob)
+      const a = window.document.createElement('a')
+      a.href = url
+      a.download = filename
+      window.document.body.appendChild(a)
+      a.click()
+      window.document.body.removeChild(a)
+      URL.revokeObjectURL(url)
+
+      onClose()
+    } catch (error) {
+      console.error('Export failed:', error)
+      alert('Export fehlgeschlagen. Bitte versuchen Sie es erneut.')
+    } finally {
+      setIsExporting(false)
+    }
+  }
+
+  const handleSave = async () => {
+    setIsExporting(true)
+    try {
+      await saveDocument()
+      alert('Dokument gespeichert!')
+    } catch (error) {
+      console.error('Save failed:', error)
+      alert('Speichern fehlgeschlagen.')
+    } finally {
+      setIsExporting(false)
+    }
+  }
+
+  if (!isOpen) return null
+
+  // Glassmorphism styles
+  const overlayStyle = 'fixed inset-0 bg-black/50 backdrop-blur-sm z-50'
+  const modalStyle = isDark
+    ? 'backdrop-blur-xl bg-white/10 border border-white/20'
+    : 'backdrop-blur-xl bg-white/90 border border-black/10 shadow-2xl'
+
+  const buttonStyle = (active: boolean) => isDark
+    ? active
+      ? 'bg-purple-500/30 text-purple-300 border border-purple-400/50'
+      : 'bg-white/5 text-white/70 border border-transparent hover:bg-white/10'
+    : active
+      ? 'bg-purple-100 text-purple-700 border border-purple-300'
+      : 'bg-slate-50 text-slate-600 border border-transparent hover:bg-slate-100'
+
+  const labelStyle = isDark ? 'text-white/70' : 'text-slate-600'
+
+  return (
+    <div className={overlayStyle} onClick={onClose}>
+      <div
+        className={`fixed top-1/2 left-1/2 -translate-x-1/2 -translate-y-1/2 w-full max-w-md rounded-3xl p-6 ${modalStyle}`}
+        onClick={(e) => e.stopPropagation()}
+      >
+        {/* Header */}
+        <div className="flex items-center justify-between mb-6">
+          <div className="flex items-center gap-3">
+            <div className={`w-10 h-10 rounded-xl flex items-center justify-center ${
+              isDark ? 'bg-purple-500/20' : 'bg-purple-100'
+            }`}>
+              <svg className={`w-6 h-6 ${isDark ? 'text-purple-300' : 'text-purple-600'}`} fill="none" stroke="currentColor" viewBox="0 0 24 24">
+                <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={1.5} d="M4 16v1a3 3 0 003 3h10a3 3 0 003-3v-1m-4-4l-4 4m0 0l-4-4m4 4V4" />
+              </svg>
+            </div>
+            <div>
+              <h2 className={`text-xl font-semibold ${isDark ? 'text-white' : 'text-slate-900'}`}>
+                Exportieren
+              </h2>
+              <p className={`text-sm ${labelStyle}`}>
+                Arbeitsblatt speichern oder exportieren
+              </p>
+            </div>
+          </div>
+          <button
+            onClick={onClose}
+            className={`p-2 rounded-xl transition-colors ${
+              isDark ? 'hover:bg-white/10 text-white/70' : 'hover:bg-slate-100 text-slate-500'
+            }`}
+          >
+            <svg className="w-6 h-6" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+              <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M6 18L18 6M6 6l12 12" />
+            </svg>
+          </button>
+        </div>
+
+        {/* Save Section */}
+        <div className="mb-6">
+          <button
+            onClick={handleSave}
+            disabled={isExporting}
+            className={`w-full py-4 rounded-xl font-medium transition-all flex items-center justify-center gap-3 ${
+              isDark
+                ? 'bg-green-500/30 text-green-300 hover:bg-green-500/40'
+                : 'bg-green-600 text-white hover:bg-green-700'
+            } ${isExporting ? 'opacity-50 cursor-not-allowed' : ''}`}
+          >
+            <svg className="w-6 h-6" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+              <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M8 7H5a2 2 0 00-2 2v9a2 2 0 002 2h14a2 2 0 002-2V9a2 2 0 00-2-2h-3m-1 4l-3 3m0 0l-3-3m3 3V4" />
+            </svg>
+            Speichern
+            {isDirty && (
+              <span className={`px-2 py-0.5 rounded-full text-xs ${
+                isDark ? 'bg-yellow-500/30 text-yellow-300' : 'bg-yellow-100 text-yellow-700'
+              }`}>
+                Ungespeichert
+              </span>
+            )}
+          </button>
+        </div>
+
+        {/* Export Format Selection */}
+        <div className="mb-4">
+          <label className={`block text-sm font-medium mb-3 ${labelStyle}`}>
+            Export-Format
+          </label>
+          <div className="grid grid-cols-3 gap-3">
+            <button
+              onClick={() => setExportFormat('pdf')}
+              className={`py-4 rounded-xl transition-all flex flex-col items-center gap-2 ${buttonStyle(exportFormat === 'pdf')}`}
+            >
+              <svg className="w-8 h-8" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+                <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={1.5} d="M7 21h10a2 2 0 002-2V9.414a1 1 0 00-.293-.707l-5.414-5.414A1 1 0 0012.586 3H7a2 2 0 00-2 2v14a2 2 0 002 2z" />
+              </svg>
+              <span className="text-sm font-medium">PDF</span>
+            </button>
+
+            <button
+              onClick={() => setExportFormat('png')}
+              className={`py-4 rounded-xl transition-all flex flex-col items-center gap-2 ${buttonStyle(exportFormat === 'png')}`}
+            >
+              <svg className="w-8 h-8" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+                <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={1.5} d="M4 16l4.586-4.586a2 2 0 012.828 0L16 16m-2-2l1.586-1.586a2 2 0 012.828 0L20 14m-6-6h.01M6 20h12a2 2 0 002-2V6a2 2 0 00-2-2H6a2 2 0 00-2 2v12a2 2 0 002 2z" />
+              </svg>
+              <span className="text-sm font-medium">PNG</span>
+            </button>
+
+            <button
+              onClick={() => setExportFormat('jpg')}
+              className={`py-4 rounded-xl transition-all flex flex-col items-center gap-2 ${buttonStyle(exportFormat === 'jpg')}`}
+            >
+              <svg className="w-8 h-8" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+                <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={1.5} d="M4 16l4.586-4.586a2 2 0 012.828 0L16 16m-2-2l1.586-1.586a2 2 0 012.828 0L20 14m-6-6h.01M6 20h12a2 2 0 002-2V6a2 2 0 00-2-2H6a2 2 0 00-2 2v12a2 2 0 002 2z" />
+              </svg>
+              <span className="text-sm font-medium">JPG</span>
+            </button>
+          </div>
+        </div>
+
+        {/* Export Button */}
+        <button
+          onClick={handleExport}
+          disabled={isExporting}
+          className={`w-full py-4 rounded-xl font-medium transition-all flex items-center justify-center gap-2 ${
+            isDark
+              ? 'bg-purple-500/30 text-purple-300 hover:bg-purple-500/40'
+              : 'bg-purple-600 text-white hover:bg-purple-700'
+          } ${isExporting ? 'opacity-50 cursor-not-allowed' : ''}`}
+        >
+          {isExporting ? (
+            <>
+              <svg className="animate-spin w-5 h-5" fill="none" viewBox="0 0 24 24">
+                <circle className="opacity-25" cx="12" cy="12" r="10" stroke="currentColor" strokeWidth="4" />
+                <path className="opacity-75" fill="currentColor" d="M4 12a8 8 0 018-8V0C5.373 0 0 5.373 0 12h4zm2 5.291A7.962 7.962 0 014 12H0c0 3.042 1.135 5.824 3 7.938l3-2.647z" />
+              </svg>
+              Exportiere...
+            </>
+          ) : (
+            <>
+              <svg className="w-5 h-5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+                <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M4 16v1a3 3 0 003 3h10a3 3 0 003-3v-1m-4-4l-4 4m0 0l-4-4m4 4V4" />
+              </svg>
+              Als {exportFormat.toUpperCase()} exportieren
+            </>
+          )}
+        </button>
+      </div>
+    </div>
+  )
+}