Fix screenshare on wayland and style

[SpecialAro]

Pre-flight Checklist

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Description of Change

Fix screenshare on wayland and style component

Motivation and Context

If a user uses wayland it prompts the user twice for selecting a window (one from the native selector from the OS, and another for selecting the single available screen - after the native selection - on Ferdium). This PR removes the second prompt (the only prompt controlled by Ferdium) and instantly retrieves the only available source in the source array.

In this PR I also added some styling and fixes (so that the user sees a loading screen after pressing the screenshare feature - while he waits for the background communication between the main process and render process on getting the available streaming sources.

Tested on:

• MacOS Sonoma
• Windows 11
• Fedora 40 (Wayland)

Checklist

• My pull request is properly named
• The changes respect the code style of the project (pnpm prepare-code)
• pnpm test passes
• I tested/previewed my changes locally

Release Notes

Fixes the double prompt on screenshare when using Wayland (Linux)