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/Tests/Engines/Help/TestHelpTopicPacket.cs

@@ -4,15 +4,15 @@ using Server.Tests;
 using Server.Tests.Network;
 using Xunit;
 
-namespace UOContent.Tests
+namespace UOContent.Tests;
+
+public class TestHelpTopicPacket
 {
-    public class TestHelpTopicPacket
+    [Theory]
+    [InlineData(HelpTopic.Healing, false)]
+    [InlineData(HelpTopic.EmptyingBowl, true)]
+    public void TestDisplayHelpTopic(int topic, bool display)
     {
-        [Theory]
-        [InlineData(HelpTopic.Healing, false)]
-        [InlineData(HelpTopic.EmptyingBowl, true)]
-        public void TestDisplayHelpTopic(int topic, bool display)
-        {
             var expected = new DisplayHelpTopic(topic, display).Compile();
 
             var ns = PacketTestUtilities.CreateTestNetState();
@@ -21,5 +21,4 @@ namespace UOContent.Tests
         var result = ns.SendPipe.Reader.AvailableToRead();
         AssertThat.Equal(result, expected);
         }
-    }
-}
+}