feat(2.0): Phase 5 — Betrieb, Observability + Politur

Backup: services/backup.py (Memory-SQLite inkl. WAL/SHM + Configs, retain 7)
+ deploy/backup.sh + POST /api/system/backup + GET /api/system/backups.
Services-Health: GET /api/system/services (aggregierte Reachability +
Observability-Links). Frontend: SystemView mit Dienste-Health + Backup-
Button + Links; Theme-Toggle (Hell/Dunkel, persistent).

Lokal verifiziert: Backup-Snapshot + services-Aggregat (TestClient),
Frontend-Build + Browser (Light-Mode bestaetigt via computed styles).
Damit Phasen 0-5 lokal fertig. Docs aktualisiert.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

backend/routers/system.py

@@ -11,6 +11,11 @@ import subprocess
 from fastapi import APIRouter, HTTPException
 from pydantic import BaseModel
 
+from config import GATEWAY_URL, HERMES_API_URL, HERMES_WEBUI_URL, LLAMA_SWAP_URL
+from services import backup as backup_svc
+from services.agent import agent_status
+from services.gateway import gateway_reachable
+from services.llamaswap import engine_reachable
 from services.system import system_status
 
 router = APIRouter(prefix="/api")
@@ -26,6 +31,35 @@ def status() -> dict:
     return system_status()
 
 
+@router.get("/system/services")
+def services() -> dict:
+    """Aggregierte Erreichbarkeit aller Stack-Dienste (für die Health-Anzeige)."""
+    a = agent_status()
+    return {
+        "services": [
+            {"name": "Engine (llama-swap)", "url": LLAMA_SWAP_URL, "ok": engine_reachable()},
+            {"name": "Gateway (LiteLLM)", "url": GATEWAY_URL, "ok": gateway_reachable()},
+            {"name": "Hermes-Gateway", "url": HERMES_API_URL, "ok": a["gateway_reachable"]},
+            {"name": "Hermes-WebUI", "url": HERMES_WEBUI_URL, "ok": a["webui_reachable"]},
+        ],
+        "links": {
+            "engine_ui": f"{LLAMA_SWAP_URL}/ui",
+            "gateway": GATEWAY_URL,
+            "hermes_webui": HERMES_WEBUI_URL,
+        },
+    }
+
+
+@router.post("/system/backup")
+def backup() -> dict:
+    return backup_svc.backup_now()
+
+
+@router.get("/system/backups")
+def backups() -> dict:
+    return {"backups": backup_svc.list_backups()}
+
+
 def _run(cmd: list[str], cwd: str | None = None) -> dict:
     try:
         p = subprocess.run(cmd, cwd=cwd, capture_output=True, text=True, timeout=180)