Fix service control buttons: sudo, real error output, UX feedback

- services.go: use sudo systemctl so bee user can control system services
- api.go: always return 200 with output field even on error, so the
  frontend shows the actual systemctl message instead of "exit status 1"
- pages.go: button shows "..." while pending then restores label;
  output panel is full-width under the table with ✓/✗ status indicator;
  output auto-scrolls to bottom

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

audit/internal/webui/api.go

@@ -383,11 +383,13 @@ func (h *handler) handleAPIServicesAction(w http.ResponseWriter, r *http.Request
 		return
 	}
 	result, err := h.opts.App.ServiceActionResult(req.Name, action)
+	status := "ok"
 	if err != nil {
-		writeError(w, http.StatusInternalServerError, err.Error())
-		return
+		status = "error"
 	}
-	writeJSON(w, map[string]string{"status": "ok", "output": result.Body})
+	// Always return 200 with output so the frontend can display the actual
+	// systemctl error message instead of a generic "exit status 1".
+	writeJSON(w, map[string]string{"status": status, "output": result.Body})
 }
 
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