use node: prefix for requires

mostly because code is being autogenerated by all the AI stuff using
this prefix. it's also used in the stack trace.

src/dockerproxy.js

@@ -6,18 +6,18 @@ exports = module.exports = {
 };
 
 const apps = require('./apps.js'),
-    assert = require('assert'),
+    assert = require('node:assert'),
     constants = require('./constants.js'),
     express = require('express'),
     debug = require('debug')('box:dockerproxy'),
-    http = require('http'),
+    http = require('node:http'),
     HttpError = require('@cloudron/connect-lastmile').HttpError,
     middleware = require('./middleware'),
-    net = require('net'),
-    path = require('path'),
+    net = require('node:net'),
+    path = require('node:path'),
     paths = require('./paths.js'),
     safe = require('safetydance'),
-    util = require('util'),
+    util = require('node:util'),
     volumes = require('./volumes.js');
 
 let gHttpServer = null;