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/Server.Tests/Server.Tests.csproj

@@ -2,6 +2,7 @@
     <PropertyGroup>
         <IsPackable>false</IsPackable>
         <Configurations>Debug;Release;Analyze</Configurations>
+        <RootNamespace>Server.Tests</RootNamespace>
     </PropertyGroup>
     <ItemGroup>
         <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.10.0" />
@@ -10,9 +11,9 @@
           <PrivateAssets>all</PrivateAssets>
           <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
         </PackageReference>
-        <ProjectReference Include="..\Server\Server.csproj" />
-        <ProjectReference Include="..\UOContent\UOContent.csproj" />
+        <ProjectReference Include="..\Application\Application.csproj" />
         <DataFiles Include="$(SolutionDir)\Distribution\Data\**" />
+        <ProjectReference Include="..\UOContent\UOContent.csproj" />
     </ItemGroup>
     <Target Name="CopyData" AfterTargets="AfterBuild">
         <Copy SourceFiles="@(DataFiles)" DestinationFolder="$(OutDir)\Data\%(RecursiveDir)" />