Add a graceful Shutdown action alongside Proxmox's Start/Restart/Stop

Stop maps to Proxmox's hard power-off (/status/stop) — fine for a
crashed guest, but risky for anything with a filesystem that'd rather
flush cleanly first. Proxmox exposes a separate /status/shutdown
endpoint that asks the guest to power itself down (ACPI event for a
VM, SIGTERM-then-wait for a container), so add it as its own action
rather than overloading Stop.

- New shutdownGuest() on the Proxmox adapter, calling /status/shutdown.
- The existing generic action route/loop already dispatches by
  ${action}Guest, so adding "shutdown" to that list was enough on the
  server side — no new route needed.
- New Shutdown button next to Restart/Stop on both the Integrations
  page's guest table and a Proxmox-linked server's detail page.
  Stop's confirm prompt now explicitly points at Shutdown as the
  gentler alternative.

Verified end-to-end against a mock Proxmox server: the shutdown call
hits /status/shutdown (never /status/stop) and is audit-logged as
shutdown_guest.

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

web/src/api/client.ts

@@ -643,6 +643,8 @@ export const api = {
         request<void>(`/api/integrations/${integrationId}/proxmox/nodes/${node}/${type}/${vmid}/stop`, { method: "POST" }),
       restart: (integrationId: number, node: string, type: ProxmoxGuestType, vmid: number) =>
         request<void>(`/api/integrations/${integrationId}/proxmox/nodes/${node}/${type}/${vmid}/restart`, { method: "POST" }),
+      shutdown: (integrationId: number, node: string, type: ProxmoxGuestType, vmid: number) =>
+        request<void>(`/api/integrations/${integrationId}/proxmox/nodes/${node}/${type}/${vmid}/shutdown`, { method: "POST" }),
     },
     synology: {
       storage: (integrationId: number) => request<SynologyStorageResponse>(`/api/integrations/${integrationId}/synology/storage`),

web/src/pages/Integrations.tsx

@@ -361,9 +361,10 @@ export default function Integrations({ user }: { user: CurrentUser }) {
     }
   }
 
-  async function guestAction(g: ProxmoxGuest, action: "start" | "stop" | "restart") {
+  async function guestAction(g: ProxmoxGuest, action: "start" | "stop" | "restart" | "shutdown") {
     if (!selectedId) return;
-    if (action === "stop" && !confirm(`Stop ${g.type === "qemu" ? "VM" : "container"} "${g.name}"?`)) return;
+    if (action === "stop" && !confirm(`Stop ${g.type === "qemu" ? "VM" : "container"} "${g.name}" immediately? Use Shutdown instead for a graceful power-off.`))
+      return;
     setActingOnGuest(g.vmid);
     setProxmoxError(null);
     try {
@@ -845,6 +846,13 @@ export default function Integrations({ user }: { user: CurrentUser }) {
                                       >
                                         Restart
                                       </button>
+                                      <button
+                                        className="btn btn-sm"
+                                        onClick={() => guestAction(g, "shutdown")}
+                                        disabled={actingOnGuest === g.vmid}
+                                      >
+                                        Shutdown
+                                      </button>
                                       <button
                                         className="btn btn-sm btn-outline-danger"
                                         onClick={() => guestAction(g, "stop")}

web/src/pages/ServerDetail.tsx

@@ -230,9 +230,10 @@ export default function ServerDetail({ user }: { user: CurrentUser }) {
 
   const { server, hardware, ipAddresses, dnsMatches } = detail;
 
-  async function guestAction(action: "start" | "stop" | "restart") {
+  async function guestAction(action: "start" | "stop" | "restart" | "shutdown") {
     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;
+    if (action === "stop" && !confirm(`Stop ${server.name} immediately? This is a hard power-off, not a graceful shutdown — use Shutdown instead if the guest OS should get a chance to close down cleanly.`))
+      return;
     setActingOnGuest(true);
     setGuestActionError(null);
     try {
@@ -371,6 +372,9 @@ export default function ServerDetail({ user }: { user: CurrentUser }) {
                             <button className="btn btn-sm" onClick={() => guestAction("restart")} disabled={actingOnGuest}>
                               Restart
                             </button>
+                            <button className="btn btn-sm" onClick={() => guestAction("shutdown")} disabled={actingOnGuest}>
+                              Shutdown
+                            </button>
                             <button
                               className="btn btn-sm btn-outline-danger"
                               onClick={() => guestAction("stop")}