feat: Screen share settings UI modal

[Dadadah]

This PR adds a screen share settings UI modal that pops up after choosing what window/screen to stream. It allows you to choose a screen share quality. Right now it only supports 720p@30fps, 1080p@30fps and Source@5fps. These values will only show up if the server is configured to allow streams of that size. The Source@5fps quality setting will cap the width and height to the configured limit, unless the limit is 0. The modal has a checkbox to not show the modal again. If you check this box, it will save your choice and disable the modal. You can enable it in the settings. You can also change the default screen share resolution chosen in the settings. The Voice settings section has been renamed to Voice & Video.

Requires stoatchat/javascript-client-sdk#149
Requires #1112

This PR is blocking #1070 and #1068

Closes #1069

How was this PR tested?

Shared screen from one client to another. Shared multiple screen resolutions and both landscape and portrait screens.

Simulated low resolution cap to ensure only low quality streaming was allowed (720p).

Screenshots & Screencasts (if appropriate)

In action:

Screencast.from.2026-04-11.17-18-42.webm

Settings UI:

Available resolutions:

Known Issues

• If a Stoat instance has a video resolution limit that is abnormal (ie. not a standard) it may result in undesired results.
• If a user attempts to start a stream with a weird aspect ratio, that user may get kicked.
  • Unsure on a proper solution for this, if a user starts the stream at a normal aspect ratio and makes it weird they will not get kicked.
• New user limitations are not respected
  • Unsure if it's possible to get if a user is new currently - may also depend on the server?
    • skill issue?
• Once a stream is started, it's quality cannot currently be changed.
  • Out of scope for this PR. Could be done separately later.

Checklist:

• I have carefully read the contributing guidelines
• I have performed a self-review of my own code
• I have made corresponding changes to the documentation if applicable
• I have no unrelated changes in the PR
• I have confirmed that any new dependencies are strictly necessary
• I have written tests for new code (if applicable)
• I have followed naming conventions/patterns in the surrounding code

Please declare, if any, LLM usage involved in creating this PR

Generative AI was not used in the creation of this PR.

[Dadadah]

I know the diff looks big here, but I actually just wrapped this in a big show block to disable showing screen shares if they're muted (as is the case when a screen share is getting configured)