Move to .NET8

- Change TFM and LangVersion
- Better exception throwing (CA1510, CA1512, CA1513)
- Better exception utility method definition (CA1859)
- Prefer comparing `.Count` over calling `.Any()` (CA1860)
- Prefer `.AsSpan()` over `.Substring()` (CA1846)
- Add a few more `scoped`
- Use `RuntimeHelpers.GetUninitializedObject()` instead of `FormatterServices.GetUninitializedObject()`
- Use delegate instead of delegate pointer in variant generic conversions
- Enable EnforceExtendedAnalyzerRules in source generator projects
- Disable CS8981 on structs named movable in Godot.NativeInterop

modules/mono/editor/GodotTools/GodotTools.ProjectEditor/GodotTools.ProjectEditor.csproj

@@ -1,17 +1,21 @@
 <Project Sdk="Microsoft.NET.Sdk">
+
   <PropertyGroup>
     <ProjectGuid>{A8CDAD94-C6D4-4B19-A7E7-76C53CC92984}</ProjectGuid>
-    <TargetFramework>net7.0</TargetFramework>
-    <LangVersion>10</LangVersion>
+    <TargetFramework>net8.0</TargetFramework>
+    <LangVersion>12</LangVersion>
     <Nullable>enable</Nullable>
   </PropertyGroup>
+
   <ItemGroup>
     <PackageReference Include="Microsoft.Build" Version="15.1.548" ExcludeAssets="runtime" />
     <PackageReference Include="Microsoft.Build.Locator" Version="1.2.6" />
     <PackageReference Include="Microsoft.NETFramework.ReferenceAssemblies" Version="1.0.0" PrivateAssets="All" />
   </ItemGroup>
+
   <ItemGroup>
     <ProjectReference Include="..\GodotTools.Core\GodotTools.Core.csproj" />
     <ProjectReference Include="..\GodotTools.Shared\GodotTools.Shared.csproj" />
   </ItemGroup>
+
 </Project>