feat: Splits Server in Core and Application (#1806)

> [!Note]
> **Developer Note**
> Now developers will only need to build/run the Application project instead of everything.
> When adding new projects, make sure to: 
> 1. Add a reference to that project in the Application project.
> 2. Add the dll file to the Distribution/Data/assemblies.json file

### Summary
- Adds an application project
- Consolidates process restarts to use `Core.Kill(true)`
- Removes some old messaging, for example processor optimization
- Fixes missing build cleanup

Projects/UOContent.Tests/UOContent.Tests.csproj

@@ -10,9 +10,8 @@
             <PrivateAssets>all</PrivateAssets>
             <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
         </PackageReference>
-        <ProjectReference Include="..\Server\Server.csproj" />
+        <ProjectReference Include="..\Application\Application.csproj" />
         <ProjectReference Include="..\Server.Tests\Server.Tests.csproj" />
-        <ProjectReference Include="..\UOContent\UOContent.csproj" />
         <DataFiles Include="$(SolutionDir)\Distribution\Data\**" />
     </ItemGroup>
     <Target Name="CopyData" AfterTargets="AfterBuild">