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>

backend/jitsi_proxy.py

@@ -0,0 +1,96 @@
+"""
+Jitsi Reverse Proxy
+
+Leitet Anfragen an den internen Jitsi-Web Container weiter,
+sodass Jitsi über Port 8000 erreichbar ist.
+"""
+
+import httpx
+from fastapi import APIRouter, Request, Response
+from fastapi.responses import StreamingResponse
+import os
+
+router = APIRouter()
+
+JITSI_INTERNAL_URL = os.getenv("JITSI_INTERNAL_URL", "http://jitsi-web:80")
+
+# HTTP Client mit längeren Timeouts für Streaming
+client = httpx.AsyncClient(
+    base_url=JITSI_INTERNAL_URL,
+    timeout=httpx.Timeout(30.0, connect=10.0),
+    follow_redirects=True
+)
+
+
+@router.api_route("/jitsi/{path:path}", methods=["GET", "POST", "PUT", "DELETE", "OPTIONS", "HEAD"])
+async def proxy_jitsi(request: Request, path: str):
+    """
+    Proxy all requests to Jitsi Web container.
+
+    This allows accessing Jitsi through the main backend port (8000)
+    instead of a separate port (8443).
+    """
+    # Build target URL
+    url = f"/{path}"
+    if request.query_params:
+        url += f"?{request.query_params}"
+
+    # Forward headers (except Host)
+    headers = dict(request.headers)
+    headers.pop("host", None)
+    headers.pop("content-length", None)
+
+    # Get request body if present
+    body = await request.body() if request.method in ["POST", "PUT"] else None
+
+    try:
+        # Forward request to Jitsi
+        response = await client.request(
+            method=request.method,
+            url=url,
+            headers=headers,
+            content=body
+        )
+
+        # Build response headers
+        response_headers = dict(response.headers)
+        # Remove headers that shouldn't be forwarded
+        for header in ["content-encoding", "content-length", "transfer-encoding"]:
+            response_headers.pop(header, None)
+
+        return Response(
+            content=response.content,
+            status_code=response.status_code,
+            headers=response_headers,
+            media_type=response.headers.get("content-type")
+        )
+
+    except httpx.ConnectError:
+        return Response(
+            content="Jitsi service not available. Please start with: docker compose up -d jitsi-web",
+            status_code=503,
+            media_type="text/plain"
+        )
+    except Exception as e:
+        return Response(
+            content=f"Proxy error: {str(e)}",
+            status_code=502,
+            media_type="text/plain"
+        )
+
+
+@router.get("/jitsi-status")
+async def jitsi_status():
+    """Check if Jitsi is available."""
+    try:
+        response = await client.get("/")
+        return {
+            "status": "available",
+            "internal_url": JITSI_INTERNAL_URL
+        }
+    except Exception as e:
+        return {
+            "status": "unavailable",
+            "error": str(e),
+            "internal_url": JITSI_INTERNAL_URL
+        }