Add Proxmox integration

Fifth live integration: VM/LXC status across every online node in the
cluster, with start/stop/restart actions — matching the "dashboard + basic
actions" depth from the plan. Adapter built against Proxmox VE's own
published API tree (pve.proxmox.com/pve-docs/api-viewer/apidoc.js — parsed
its ~4MB ExtJS tree structure directly since it's not plain JSON) plus
community-verified docs for the token auth header format, since the user's
instance isn't reachable from here.

server/src/integrations/proxmox/adapter.ts: GET /nodes for online nodes,
then GET /nodes/{node}/{qemu,lxc} per node in parallel (Promise.all) and
flattened, tagging each guest with its node and type; POST
/nodes/{node}/{qemu,lxc}/{vmid}/status/{start,stop,reboot} for actions (all
confirmed token-auth-eligible via the spec's "allowtoken" flag). Uses
node:https directly (like the cPanel DNS adapter) rather than fetch, since
Proxmox commonly runs a self-signed certificate in homelab setups — added
an "Allow self-signed certificate" checkbox field for that. Auth is
`Authorization: PVEAPIToken=<tokenId>=<tokenSecret>`, a different shape
from the other three integrations' single bearer token, so the field
schema splits it into two fields (a non-secret token ID like
"root@pam!homelab-manager" and a secret token value).

Verified: full build passes. Unreachable from here, so ran a 16-check HTTP
test against the live server: role gating, credential non-leakage,
disabled-integration blocking, invalid-guest-type and non-numeric-vmid
rejection, checkbox-only config correctly still failing required-field
validation, and the wrong_type crash-safety check for this fifth adapter
type — server stays up throughout. Real node/VM data and the actual
start/stop/restart actions still need verification once this app can reach
the user's Proxmox cluster.

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

web/src/api/client.ts

@@ -271,6 +271,25 @@ export interface SemaphoreTemplatesResponse {
   summary: { total: number; failing: number };
 }
 
+export type ProxmoxGuestType = "qemu" | "lxc";
+
+export interface ProxmoxGuest {
+  vmid: number;
+  name: string;
+  node: string;
+  type: ProxmoxGuestType;
+  status: string;
+  cpu: number | null;
+  maxmem: number | null;
+  mem: number | null;
+  uptime: number | null;
+}
+
+export interface ProxmoxGuestsResponse {
+  guests: ProxmoxGuest[];
+  summary: { total: number; running: number };
+}
+
 export class UnauthorizedError extends Error {}
 export class ForbiddenError extends Error {}
 
@@ -477,5 +496,14 @@ export const api = {
           { method: "POST" },
         ),
     },
+    proxmox: {
+      guests: (integrationId: number) => request<ProxmoxGuestsResponse>(`/api/integrations/${integrationId}/proxmox/guests`),
+      start: (integrationId: number, node: string, type: ProxmoxGuestType, vmid: number) =>
+        request<void>(`/api/integrations/${integrationId}/proxmox/nodes/${node}/${type}/${vmid}/start`, { method: "POST" }),
+      stop: (integrationId: number, node: string, type: ProxmoxGuestType, vmid: number) =>
+        request<void>(`/api/integrations/${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" }),
+    },
   },
 };