The dev server was ignoring the `sourceMap` configuration from angular.json,
always injecting inline source maps into all served files. This affected both
CSS (hardcoded `devSourcemap: true`) and JavaScript (prebundle transformer
hardcoded `sourcemap: true`), causing 2-3x file size inflation even when
source maps were explicitly disabled.

The fix passes the normalized `scripts` and `styles` source map settings
through to the Vite configuration, so that `css.devSourcemap` and the
prebundle transformer respect the user's `sourceMap` setting.

Closes angular#31331