infra: Migrate to .NET 7 (#3795)

* Update readme to mention .NET 7

* infra: Migrate to .NET 7

.NET 7 is still in preview but this prepare for the release coming up
next month.

* Use Random.Shared in CreateRandom

* Move UInt128Utils.cs to Ryujinx.Common project

* Fix inverted parameters in System.UInt128 constructor

* Fix Visual Studio complains on  Ryujinx.Graphics.Vic

* time: Fix missing alignment enforcement in SystemClockContext

Fixes at least Smash

* time: Fix missing alignment enforcement in SteadyClockContext

Fix games (like recent version of Smash) using time shared memory

* Switch to .NET 7.0.100 release

* Enable Tiered PGO

* Ensure CreateId validity requirements are meet when doing random generation

Also enforce correct packing layout for other Mii structures.

This fix a Mario Kart 8 crashes related to the default Miis.

Ryujinx.Graphics.Vic/Image/SurfaceReader.cs

@@ -229,8 +229,8 @@ namespace Ryujinx.Graphics.Vic.Image
 
         private static RentedBuffer ReadBuffer(
             ResourceManager rm,
-            ref SlotConfig config,
-            ref Array8<PlaneOffsets> offsets,
+            scoped ref SlotConfig config,
+            scoped ref Array8<PlaneOffsets> offsets,
             bool linear,
             int plane,
             int width,