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/app/api/uploads/route.ts

@@ -0,0 +1,115 @@
+import { NextRequest, NextResponse } from 'next/server'
+import { writeFile, readFile, mkdir } from 'fs/promises'
+import { existsSync } from 'fs'
+import path from 'path'
+
+// Speicherort fuer Uploads
+const UPLOADS_DIR = '/tmp/breakpilot-uploads'
+const METADATA_FILE = path.join(UPLOADS_DIR, 'metadata.json')
+
+interface UploadedFile {
+  id: string
+  sessionId: string
+  name: string
+  type: string
+  size: number
+  uploadedAt: string
+  dataUrl: string // Base64 data URL
+}
+
+// Stelle sicher, dass das Upload-Verzeichnis existiert
+async function ensureUploadsDir() {
+  if (!existsSync(UPLOADS_DIR)) {
+    await mkdir(UPLOADS_DIR, { recursive: true })
+  }
+}
+
+// Lade Metadaten
+async function loadMetadata(): Promise<UploadedFile[]> {
+  try {
+    await ensureUploadsDir()
+    if (existsSync(METADATA_FILE)) {
+      const data = await readFile(METADATA_FILE, 'utf-8')
+      return JSON.parse(data)
+    }
+  } catch (error) {
+    console.error('Error loading metadata:', error)
+  }
+  return []
+}
+
+// Speichere Metadaten
+async function saveMetadata(uploads: UploadedFile[]) {
+  await ensureUploadsDir()
+  await writeFile(METADATA_FILE, JSON.stringify(uploads, null, 2))
+}
+
+// GET: Liste alle Uploads fuer eine Session
+export async function GET(request: NextRequest) {
+  const sessionId = request.nextUrl.searchParams.get('sessionId')
+
+  const uploads = await loadMetadata()
+
+  if (sessionId) {
+    const filtered = uploads.filter(u => u.sessionId === sessionId)
+    return NextResponse.json({ uploads: filtered })
+  }
+
+  // Alle Uploads (fuer Dashboard)
+  return NextResponse.json({ uploads })
+}
+
+// POST: Neuen Upload hinzufuegen
+export async function POST(request: NextRequest) {
+  try {
+    const body = await request.json()
+    const { sessionId, name, type, size, dataUrl } = body
+
+    if (!sessionId || !name || !dataUrl) {
+      return NextResponse.json(
+        { error: 'Missing required fields' },
+        { status: 400 }
+      )
+    }
+
+    const upload: UploadedFile = {
+      id: `upload-${Date.now()}-${Math.random().toString(36).substr(2, 9)}`,
+      sessionId,
+      name,
+      type: type || 'application/octet-stream',
+      size: size || 0,
+      uploadedAt: new Date().toISOString(),
+      dataUrl
+    }
+
+    const uploads = await loadMetadata()
+    uploads.push(upload)
+    await saveMetadata(uploads)
+
+    return NextResponse.json({ success: true, upload })
+  } catch (error) {
+    console.error('Upload error:', error)
+    return NextResponse.json(
+      { error: 'Upload failed' },
+      { status: 500 }
+    )
+  }
+}
+
+// DELETE: Upload loeschen
+export async function DELETE(request: NextRequest) {
+  const id = request.nextUrl.searchParams.get('id')
+
+  if (!id) {
+    return NextResponse.json(
+      { error: 'Missing upload id' },
+      { status: 400 }
+    )
+  }
+
+  const uploads = await loadMetadata()
+  const filtered = uploads.filter(u => u.id !== id)
+  await saveMetadata(filtered)
+
+  return NextResponse.json({ success: true })
+}