Add start/restart/stop buttons to Proxmox-linked servers' detail page

The Proxmox start/stop/restart routes already existed (used by the
Integrations page's guest table) but weren't reachable from a server's
own detail page, even when that server was linked to a Proxmox guest.

Reuses the existing POST /api/integrations/:id/proxmox/nodes/:node/
:type/:vmid/{start,stop,restart} routes and the operator+ role gate
already enforced there — no server-side changes needed. Buttons only
render for hardware.source === "proxmox", mirroring the Integrations
page's running/stopped button-set logic, with the same confirm-before-
stop prompt for the non-reversible action.

Verified end-to-end against the real dev server with a mock Proxmox
HTTPS server: linked a server to a mock guest, confirmed the detail
endpoint's live status, then triggered restart/stop/start and
confirmed the mock actually received each action and every call was
audit-logged.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

web/src/pages/ServerDetail.tsx

@@ -79,6 +79,9 @@ export default function ServerDetail({ user }: { user: CurrentUser }) {
   const [linking, setLinking] = useState(false);
   const [linkError, setLinkError] = useState<string | null>(null);
 
+  const [actingOnGuest, setActingOnGuest] = useState(false);
+  const [guestActionError, setGuestActionError] = useState<string | null>(null);
+
   const loadDetail = useCallback(() => {
     setRefreshing(true);
     return api.servers
@@ -227,6 +230,26 @@ export default function ServerDetail({ user }: { user: CurrentUser }) {
 
   const { server, hardware, ipAddresses, dnsMatches } = detail;
 
+  async function guestAction(action: "start" | "stop" | "restart") {
+    if (!server.proxmoxIntegrationId || !server.proxmoxNode || !server.proxmoxGuestType || server.proxmoxVmid === null) return;
+    if (action === "stop" && !confirm(`Stop ${server.name}? This is an immediate power-off, not a graceful shutdown.`)) return;
+    setActingOnGuest(true);
+    setGuestActionError(null);
+    try {
+      await api.integrations.proxmox[action](
+        server.proxmoxIntegrationId,
+        server.proxmoxNode,
+        server.proxmoxGuestType,
+        server.proxmoxVmid,
+      );
+      await loadDetail();
+    } catch (err) {
+      setGuestActionError(err instanceof Error ? err.message : String(err));
+    } finally {
+      setActingOnGuest(false);
+    }
+  }
+
   return (
     <>
       <div className="mb-3">
@@ -330,7 +353,41 @@ export default function ServerDetail({ user }: { user: CurrentUser }) {
               {hardware.error && <div className="alert alert-danger">{hardware.error}</div>}
               {hardware.source === "proxmox" && !hardware.error && (
                 <>
-                  <div className="text-secondary small mb-3">Synced live from Proxmox just now.</div>
+                  <div className="d-flex align-items-center justify-content-between mb-3">
+                    <div className="text-secondary small">
+                      Synced live from Proxmox just now.
+                      {hardware.status && (
+                        <span
+                          className={`badge ms-2 ${hardware.status === "running" ? "bg-green-lt text-green" : "bg-secondary-lt text-secondary"}`}
+                        >
+                          {hardware.status}
+                        </span>
+                      )}
+                    </div>
+                    {canEditTasks && (
+                      <div className="btn-list flex-nowrap">
+                        {hardware.status === "running" ? (
+                          <>
+                            <button className="btn btn-sm" onClick={() => guestAction("restart")} disabled={actingOnGuest}>
+                              Restart
+                            </button>
+                            <button
+                              className="btn btn-sm btn-outline-danger"
+                              onClick={() => guestAction("stop")}
+                              disabled={actingOnGuest}
+                            >
+                              Stop
+                            </button>
+                          </>
+                        ) : (
+                          <button className="btn btn-sm btn-primary" onClick={() => guestAction("start")} disabled={actingOnGuest}>
+                            Start
+                          </button>
+                        )}
+                      </div>
+                    )}
+                  </div>
+                  {guestActionError && <div className="alert alert-danger">{guestActionError}</div>}
                   <div className="row g-3">
                     <div className="col-sm-6">
                       <div className="text-secondary small">CPU</div>