feat(hp): Add displayArea option for Hanging protocols and example with Mamo(#3808)

platform/app/.webpack/webpack.pwa.js

@@ -20,6 +20,7 @@ const PUBLIC_URL = process.env.PUBLIC_URL || '/';
 const APP_CONFIG = process.env.APP_CONFIG || 'config/default.js';
 const PROXY_TARGET = process.env.PROXY_TARGET;
 const PROXY_DOMAIN = process.env.PROXY_DOMAIN;
+const OHIF_PORT = Number(process.env.OHIF_PORT || 3000);
 const ENTRY_TARGET = process.env.ENTRY_TARGET || `${SRC_DIR}/index.js`;
 const Dotenv = require('dotenv-webpack');
 const writePluginImportFile = require('./writePluginImportsFile.js');
@@ -143,7 +144,7 @@ module.exports = (env, argv) => {
       // http2: true,
       // https: true,
       open: true,
-      port: 3000,
+      port: OHIF_PORT,
       client: {
         overlay: { errors: true, warnings: false },
       },