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/QRCodeUpload.tsx

@@ -0,0 +1,334 @@
+'use client'
+
+import { useState, useEffect, useCallback } from 'react'
+import { useTheme } from '@/lib/ThemeContext'
+
+interface UploadedFile {
+  id: string
+  sessionId: string
+  name: string
+  type: string
+  size: number
+  uploadedAt: string
+  dataUrl: string
+}
+
+interface QRCodeUploadProps {
+  sessionId?: string
+  onClose?: () => void
+  onFileUploaded?: (file: UploadedFile) => void
+  onFilesChanged?: (files: UploadedFile[]) => void
+  className?: string
+}
+
+export function QRCodeUpload({
+  sessionId,
+  onClose,
+  onFileUploaded,
+  onFilesChanged,
+  className = ''
+}: QRCodeUploadProps) {
+  const { isDark } = useTheme()
+  const [qrCodeUrl, setQrCodeUrl] = useState<string | null>(null)
+  const [uploadUrl, setUploadUrl] = useState<string>('')
+  const [isLoading, setIsLoading] = useState(true)
+  const [uploadedFiles, setUploadedFiles] = useState<UploadedFile[]>([])
+  const [isPolling, setIsPolling] = useState(false)
+
+  // Format file size
+  const formatFileSize = (bytes: number): string => {
+    if (bytes === 0) return '0 B'
+    const k = 1024
+    const sizes = ['B', 'KB', 'MB', 'GB']
+    const i = Math.floor(Math.log(bytes) / Math.log(k))
+    return parseFloat((bytes / Math.pow(k, i)).toFixed(1)) + ' ' + sizes[i]
+  }
+
+  // Fetch uploads for this session
+  const fetchUploads = useCallback(async () => {
+    if (!sessionId) return
+
+    try {
+      const response = await fetch(`/api/uploads?sessionId=${sessionId}`)
+      if (response.ok) {
+        const data = await response.json()
+        const newFiles = data.uploads || []
+
+        // Check if there are new files
+        if (newFiles.length > uploadedFiles.length) {
+          const newlyAdded = newFiles.slice(uploadedFiles.length)
+          newlyAdded.forEach((file: UploadedFile) => {
+            if (onFileUploaded) {
+              onFileUploaded(file)
+            }
+          })
+        }
+
+        setUploadedFiles(newFiles)
+
+        if (onFilesChanged) {
+          onFilesChanged(newFiles)
+        }
+      }
+    } catch (error) {
+      console.error('Failed to fetch uploads:', error)
+    }
+  }, [sessionId, uploadedFiles.length, onFileUploaded, onFilesChanged])
+
+  // Initialize QR code and start polling
+  useEffect(() => {
+    // Generate Upload-URL
+    let baseUrl = typeof window !== 'undefined' ? window.location.origin : ''
+
+    // Hostname to IP mapping for local network
+    const hostnameToIP: Record<string, string> = {
+      'macmini': '192.168.178.100',
+      'macmini.local': '192.168.178.100',
+    }
+
+    // Replace known hostnames with IP addresses
+    Object.entries(hostnameToIP).forEach(([hostname, ip]) => {
+      if (baseUrl.includes(hostname)) {
+        baseUrl = baseUrl.replace(hostname, ip)
+      }
+    })
+
+    const uploadPath = `/upload/${sessionId || 'new'}`
+    const fullUrl = `${baseUrl}${uploadPath}`
+    setUploadUrl(fullUrl)
+
+    // Generate QR code via external API
+    const qrApiUrl = `https://api.qrserver.com/v1/create-qr-code/?size=300x300&data=${encodeURIComponent(fullUrl)}`
+    setQrCodeUrl(qrApiUrl)
+    setIsLoading(false)
+
+    // Initial fetch
+    fetchUploads()
+
+    // Start polling for new uploads every 3 seconds
+    setIsPolling(true)
+    const pollInterval = setInterval(() => {
+      fetchUploads()
+    }, 3000)
+
+    return () => {
+      clearInterval(pollInterval)
+      setIsPolling(false)
+    }
+  }, [sessionId]) // Note: fetchUploads is intentionally not in deps to avoid re-creating interval
+
+  // Separate effect for fetching when uploadedFiles changes
+  useEffect(() => {
+    // This is just for the callback effect, actual polling is in the other useEffect
+  }, [uploadedFiles, onFilesChanged])
+
+  const copyToClipboard = async () => {
+    try {
+      await navigator.clipboard.writeText(uploadUrl)
+      alert('Link kopiert!')
+    } catch (err) {
+      console.error('Kopieren fehlgeschlagen:', err)
+    }
+  }
+
+  const deleteUpload = async (id: string) => {
+    try {
+      const response = await fetch(`/api/uploads?id=${id}`, { method: 'DELETE' })
+      if (response.ok) {
+        const newFiles = uploadedFiles.filter(f => f.id !== id)
+        setUploadedFiles(newFiles)
+        if (onFilesChanged) {
+          onFilesChanged(newFiles)
+        }
+      }
+    } catch (error) {
+      console.error('Failed to delete upload:', error)
+    }
+  }
+
+  return (
+    <div className={`${className}`}>
+      <div className={`rounded-3xl border p-6 ${
+        isDark ? 'bg-white/10 border-white/20' : 'bg-white border-slate-200 shadow-lg'
+      }`}>
+        {/* 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'
+            }`}>
+              <span className="text-xl">📱</span>
+            </div>
+            <div>
+              <h3 className={`font-semibold ${isDark ? 'text-white' : 'text-slate-900'}`}>
+                Mit Mobiltelefon hochladen
+              </h3>
+              <p className={`text-sm ${isDark ? 'text-white/50' : 'text-slate-500'}`}>
+                QR-Code scannen oder Link teilen
+              </p>
+            </div>
+          </div>
+          {onClose && (
+            <button
+              onClick={onClose}
+              className={`p-2 rounded-lg transition-colors ${
+                isDark ? 'hover:bg-white/10 text-white/60' : 'hover:bg-slate-100 text-slate-400'
+              }`}
+            >
+              <svg className="w-5 h-5" 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>
+
+        {/* QR Code */}
+        <div className="flex flex-col items-center">
+          <div className={`p-4 rounded-2xl ${isDark ? 'bg-white' : 'bg-slate-50'}`}>
+            {isLoading ? (
+              <div className="w-[200px] h-[200px] flex items-center justify-center">
+                <div className="w-8 h-8 border-2 border-purple-500 border-t-transparent rounded-full animate-spin" />
+              </div>
+            ) : qrCodeUrl ? (
+              <img
+                src={qrCodeUrl}
+                alt="QR Code zum Hochladen"
+                className="w-[200px] h-[200px]"
+              />
+            ) : (
+              <div className="w-[200px] h-[200px] flex items-center justify-center text-slate-400">
+                QR-Code nicht verfuegbar
+              </div>
+            )}
+          </div>
+
+          <p className={`mt-4 text-center text-sm ${isDark ? 'text-white/60' : 'text-slate-600'}`}>
+            Scannen Sie diesen Code mit Ihrem Handy,<br />
+            um Dokumente direkt hochzuladen.
+          </p>
+
+          {/* Polling indicator */}
+          {isPolling && (
+            <div className={`mt-2 flex items-center gap-2 text-xs ${isDark ? 'text-white/40' : 'text-slate-400'}`}>
+              <div className="w-2 h-2 bg-green-500 rounded-full animate-pulse" />
+              Warte auf Uploads...
+            </div>
+          )}
+        </div>
+
+        {/* Uploaded Files List */}
+        {uploadedFiles.length > 0 && (
+          <div className={`mt-6 p-4 rounded-xl ${
+            isDark ? 'bg-green-500/10 border border-green-500/20' : 'bg-green-50 border border-green-200'
+          }`}>
+            <div className="flex items-center justify-between mb-3">
+              <p className={`text-sm font-medium ${isDark ? 'text-green-300' : 'text-green-700'}`}>
+                {uploadedFiles.length} Datei{uploadedFiles.length !== 1 ? 'en' : ''} empfangen
+              </p>
+            </div>
+            <div className="space-y-2 max-h-40 overflow-y-auto">
+              {uploadedFiles.map((file) => (
+                <div
+                  key={file.id}
+                  className={`flex items-center gap-3 p-2 rounded-lg ${
+                    isDark ? 'bg-white/5' : 'bg-white'
+                  }`}
+                >
+                  <span className="text-lg">
+                    {file.type.startsWith('image/') ? '🖼️' : '📄'}
+                  </span>
+                  <div className="flex-1 min-w-0">
+                    <p className={`text-sm font-medium truncate ${isDark ? 'text-white' : 'text-slate-900'}`}>
+                      {file.name}
+                    </p>
+                    <p className={`text-xs ${isDark ? 'text-white/50' : 'text-slate-500'}`}>
+                      {formatFileSize(file.size)}
+                    </p>
+                  </div>
+                  <button
+                    onClick={() => deleteUpload(file.id)}
+                    className={`p-1 rounded transition-colors ${
+                      isDark ? 'hover:bg-red-500/20 text-red-400' : 'hover:bg-red-100 text-red-500'
+                    }`}
+                  >
+                    <svg className="w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+                      <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M19 7l-.867 12.142A2 2 0 0116.138 21H7.862a2 2 0 01-1.995-1.858L5 7m5 4v6m4-6v6m1-10V4a1 1 0 00-1-1h-4a1 1 0 00-1 1v3M4 7h16" />
+                    </svg>
+                  </button>
+                </div>
+              ))}
+            </div>
+          </div>
+        )}
+
+        {/* Link teilen */}
+        <div className="mt-6">
+          <p className={`text-xs mb-2 ${isDark ? 'text-white/40' : 'text-slate-400'}`}>
+            Oder Link teilen:
+          </p>
+          <div className="flex items-center gap-2">
+            <input
+              type="text"
+              value={uploadUrl}
+              readOnly
+              className={`flex-1 px-3 py-2 rounded-xl text-sm border ${
+                isDark
+                  ? 'bg-white/5 border-white/10 text-white/80'
+                  : 'bg-slate-50 border-slate-200 text-slate-700'
+              }`}
+            />
+            <button
+              onClick={copyToClipboard}
+              className={`px-4 py-2 rounded-xl text-sm font-medium transition-colors ${
+                isDark
+                  ? 'bg-white/10 text-white hover:bg-white/20'
+                  : 'bg-slate-200 text-slate-700 hover:bg-slate-300'
+              }`}
+            >
+              Kopieren
+            </button>
+          </div>
+        </div>
+
+        {/* Network hint - only show if no files uploaded yet */}
+        {uploadedFiles.length === 0 && (
+          <div className={`mt-6 p-4 rounded-xl ${
+            isDark ? 'bg-amber-500/10 border border-amber-500/20' : 'bg-amber-50 border border-amber-200'
+          }`}>
+            <div className="flex items-start gap-3">
+              <span className="text-lg">⚠️</span>
+              <div>
+                <p className={`text-sm font-medium ${isDark ? 'text-amber-300' : 'text-amber-900'}`}>
+                  Nur im lokalen Netzwerk
+                </p>
+                <p className={`text-xs mt-1 ${isDark ? 'text-amber-300/70' : 'text-amber-700'}`}>
+                  Ihr Mobiltelefon muss mit dem gleichen Netzwerk verbunden sein.
+                </p>
+              </div>
+            </div>
+          </div>
+        )}
+
+        {/* Tip */}
+        <div className={`mt-4 p-4 rounded-xl ${
+          isDark ? 'bg-blue-500/10 border border-blue-500/20' : 'bg-blue-50 border border-blue-200'
+        }`}>
+          <div className="flex items-start gap-3">
+            <span className="text-lg">💡</span>
+            <div>
+              <p className={`text-sm font-medium ${isDark ? 'text-blue-300' : 'text-blue-900'}`}>
+                Tipp: Mehrere Seiten scannen
+              </p>
+              <p className={`text-xs mt-1 ${isDark ? 'text-blue-300/70' : 'text-blue-700'}`}>
+                Sie koennen beliebig viele Fotos hochladen.
+              </p>
+            </div>
+          </div>
+        </div>
+      </div>
+    </div>
+  )
+}
+
+// Export the UploadedFile type for use in other components
+export type { UploadedFile }