Ability to use the Emulator UI from a remote development environment with port forwarding

Note: Before filing feature requests in this repo, please ensure that this is a feature request for the Emulator Suite UI. Emulator Suite and/or Firebase CLI feature requests should be filed under the firebase-tools repo here:
https://github.com/firebase/firebase-tools/issues/new/choose

**Is your feature request related to a problem? Please describe.**
A clear and concise description of what the problem is. Ex. I'm always frustrated when [...]

When using a remote development environment like Code Spaces or Cloud Workstations they forward ports as URLs like

https://some-crazy-url-464x7qrxprcqvg4-4000.preview.app.github.dev/

Where the 4000 before the domain is the port.

When running the Emulator UI, specifically the Firebase UI, it tries to connect to make a web socket connection by tacking on the web socket port like this:

https://some-crazy-url-464x7qrxprcqvg4-4000.preview.app.github.dev:9150

Unfortunately, that doesn't seem to work. I believe it needs to be something more like this:

https://some-crazy-url-464x7qrxprcqvg4-9150.preview.app.github.dev

**Describe the solution you'd like**
Maybe there's a way in the Firebase config file for a project we could set up this URL for the web socket connection?

**Describe alternatives you've considered**
I can't really think of any alternatives, but I'm open.

**Additional context**
Add any other context or screenshots about the feature request here.

Start by locating where the Firebase UI constructs its web socket URL and how the Emulator UI receives configuration. Reproduce the issue in a remote development environment with forwarded ports, then verify that the web socket connects through the forwarded-host URL rather than an appended port.

Written by the indexing model from the issue text.