@OrGranot You’re using Vite, and it doesn’t work the way that you think it does.
While you’ve used only simple HTML, CSS & JS, Vite is running a build process etc.
You should read their Static Asset Handling documentation.
Specifically the section on the public directory.
You’ll also find that you aren’t deploying the root of your repository, but rather the dist folder that Vite produces, which is why your files in the root aren’t deployed.
If you move the files into the public directory, they’ll be copied into the dist folder during build, and thus get deployed.