Allow Setting Port for shopify app dev --use-localhost

[NickWesselman]

@huykon225

hot reload seem not work when run dev with -use-localhost

You might check this thread for one potential solution:

HMR is broken: Vite shows websocket error using react embedded app when using --use-localhost

When using --use-localhost the app loads (app is embedded using react + vite) and I can see the app frontend. But I noticed that vite gives this websocket error, [Screenshot 2025-04-12 at 6.36.35 PM] After this, if I make any changes to the code, HMR is broken. Vite tries to update, but I do not see those changes in the app, it continues to show the initial load. This is almost same vite configuration and most of the code is similar to this codebase, OS: MacOS shopify.web.toml is roles =…