fix: Dokploy domain.create uses 'host' (not 'hostName') + certificateType: letsencrypt

- Field name: hostName → host (verified via direct API test)
- Added certificateType: 'letsencrypt' for automatic HTTPS cert provisioning
- Updated createDomain in dokploy.ts + custom-domain route
- HTTPS is enabled by default (https: true)
- Let's Encrypt auto-provisions certificate for the subdomain

src/app/api/aos/instances/[id]/custom-domain/route.ts

@@ -183,9 +183,10 @@ export async function PATCH(req: Request, { params }: { params: Promise<{ id: st
       try {
         await dokploy.createDomain({
           applicationId: instance.dokployAppId,
-          hostName: instance.customDomain,
+          host: instance.customDomain,
           port: 3000,
           https: true,
+          certificateType: 'letsencrypt',
         })
       } catch (e) {
         // Non-fatal — domain verification still succeeded, Dokploy attach can retry