SWA start is broken when using Vite and TypeScript

[sinedied]

Before filing this issue, please ensure you're using the latest CLI by running swa --version and comparing to the latest version on npm.

swa version: 2.0.6

Are you accessing the CLI from the default port :4280 ?

• [ ] No, I am using a different port number (--port) and accessing the CLI from that port
• [x] Yes, I am accessing the CLI from port :4280

Make sure you are accessing the URL printed in the console when running swa start!

ℹ️ NOTE: Make sure to enable debug logs when running any swa commands using --verbose=silly

Describe the bug When using latest Vite (>=6.3.5) dev server and a TypeScript project, SWA CLI fails to load through the dev proxy (:4280) while it work using the Vite dev server directly (:5173).

The issue seems to that the MIME type is changed when going through the SWA proxy, changing from text/javascript to video/m2pt.

To Reproduce Steps to reproduce the behavior:

1. Create a new project folder, and run npm create vite@latest repro -- --template lit-ts
2. cd repro && npm install && npm install -D @azure/static-web-apps-cli
3. Add this swa-cli.config.json:

{
  "$schema": "https://aka.ms/azure/static-web-apps-cli/schema",
  "configurations": {
    "registration-website": {
      "appLocation": ".",
      "run": "npm run dev",
      "appDevServerUrl": "http://localhost:5173"
    }
  }
}

4. Run npx swa start

Expected behavior Requests going through the proxy do not alter the MIME type

Desktop (please complete the following information):

• OS: MacOS
• Version 15.4.1 (24E263)