refactor: verplaats run() duplicaat naar common.py

run() stond identiek in app.py en app_system.py. Verplaatst naar
common.py als single source of truth; beide modules importeren
nu de centrale versie.

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

control/app_system.py

@@ -5,6 +5,7 @@ from fastapi import APIRouter, HTTPException
 from common import (
     _podman_get_json as _common_podman_get_json,
     _systemctl as _common_systemctl,
+    run,
 )
 
 
@@ -68,14 +69,6 @@ def init_system_router(session, podman_api_base: str, workloads_dir: str) -> API
             "api_raw_sample": api_containers[0] if isinstance(api_containers, list) and api_containers else api_containers,
         }
 
-    def run(cmd):
-        try:
-            result = subprocess.run(cmd, capture_output=True, text=True, check=False)
-            output = (result.stdout or "") + (result.stderr or "")
-            return result.returncode, output.strip()
-        except Exception as e:
-            return 1, str(e)
-
     def _systemctl(cmd):
         return _common_systemctl(cmd, run)