feat(agent): v0.3.5 Windows inbound forwarding, UI actions, lifecycle

- Configure tailscale serve automatically for each instance on Windows userspace networking.
- Add local UI buttons: start/stop/reset/delete instances (stop/start preserve volumes).
- Clean shutdown: stop tailscaled and instances, notify server with instance_stopped.
- Restart tailscaled on agent boot using persisted state when pre-auth key is absent.
- Sync instance stopped/deleted status to dashboard (server/lib/websocket.ts).
- Security: include prior authz/scoping changes across API routes, ephemeral pre-auth keys, ACL policy, internal API key.
- Update SUIVI_VPN_ONDEMAND.md and docs/ONBOARDING_CLIENT.md.
- Bump agent version to 0.3.5.

server/app/api/nodes/route.ts

@@ -1,9 +1,15 @@
 import { NextRequest, NextResponse } from "next/server";
 import { prisma } from "@/lib/prisma";
+import { requireAuth, getScopedEstablishmentId, forbidden } from "@/lib/api-auth";
 
 export async function GET(req: NextRequest) {
+  const user = await requireAuth();
+  if (user instanceof NextResponse) return user;
+
   const { searchParams } = new URL(req.url);
-  const establishmentId = searchParams.get("establishmentId");
+  const requestedId = searchParams.get("establishmentId");
+  const establishmentId = getScopedEstablishmentId(user, requestedId);
+  if (establishmentId instanceof NextResponse) return establishmentId;
 
   let where: any = {};
   if (establishmentId) {