feat(templates): support isolated = false opt-out in template.toml

Templates using network_mode: host (e.g. cloudflared) can now declare
isolated = false in their [config] section to prevent Dokploy from
injecting networks into the compose, which would cause a Docker error.

Default behavior (isolated = true) is unchanged for all existing templates.

Fixes #4366

packages/server/src/templates/github.ts

@@ -21,6 +21,7 @@ export interface CompleteTemplate {
 		[key: string]: string;
 	};
 	config: {
+		isolated?: boolean;
 		domains: Array<{
 			serviceName: string;
 			port: number;