Steps to reproduce

Set base href in document to "/"
Make a web app that uses url path strategy
Try to refresh app from "/someURL"

Expected results

main.dart.js is loaded from /main.dart.js

Actual results

/ is stripped from base url during URL resolution and main.dart.js is loaded relative to document instead of root

This regression is caused by recent changes here:

https://github.com/flutter/engine/blob/main/lib/web_ui/flutter_js/src/utils.js
https://github.com/flutter/engine/blob/main/lib/web_ui/flutter_js/src/entrypoint_loader.js

In 3.22 the / is not stripped, but in 3.24 it is stripped.

Code sample

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Logs

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Flutter Doctor output

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