[GUI] Update library page layout

[freakdaniel]

Motivation

Part of #606

The current library uses a compact cover grid and passes the selected game information in a separate launch bar. In this PR i port the self-contained library part of the redesign while keeping the broader navigation, settings and application architecture outside its scope

Changes

• Reworked the library into a horizontal cover rail
• Added hover and selection feedback for game tiles
• Added a persistent Add folder tile at the end of the library
• Moved the selected game title, title ID, version and size into a single details surface
• Removed bottom launch bar
• Combined launching and stopping into one stateful button
• Removed the loading popup and background blur shown while a game is running
• Added a close action to the embedded console panel
• Added tests for the library tile collection and Add folder tile placement (will be also needed in future after i decide about ReactiveUI and notifiers)

Testing

• dotnet build SharpEmu.slnx -c Release --no-restore
• dotnet test tests/SharpEmu.Libs.Tests/SharpEmu.Libs.Tests.csproj -c Release --no-build
• Dreaming Sarah (PPSA02929). Checked horizontal tile selection, selected game metadata, launching, stopping, button state changes and the embedded console layout
• No emulator runtime or game compatibility code was changed

Checklist

By submitting this pull request, I confirm that:

• I have read and followed CONTRIBUTING.md.
• I tested my changes or marked the testing section as N/A.
• I wrote this pull request description myself and did not paste AI-generated explanations.
• I listed the game(s) I tested (or marked the testing section as N/A).

[github-actions]

📦 Build artifacts — b19f4d4

Platform	Download
Windows (win-x64)	sharpemu-win-x64-9c120d9
Linux (linux-x64)	sharpemu-linux-x64-9c120d9
macOS (osx-x64)	sharpemu-osx-x64-9c120d9

From build run #1473. Downloads require a GitHub login and expire after 90 days.

[par274]

I think games should be in square format instead of vertical. Because in vertical format, some parts of the cover are cropped.

[freakdaniel]

I think games should be in square format instead of vertical. Because in vertical format, some parts of the cover are cropped.

Ok i'll work on it rn

[freakdaniel]

@par274 just changed cards format. In future i plan to make carousel more awesome