Refactor project structure and enhance functionality

Changed the project namespace from `Ghost.Editor` to `Ghost.App` across multiple files.
Changed the `InternalsVisibleTo` attribute in `AssemblyInfo.cs` to include `Ghost.App`.
Changed the `ProjectRepository` class to add new asynchronous methods for retrieving projects by ID, name, and metadata path.
Changed the `ProjectService` class to utilize the new asynchronous project loading methods.
Changed the `SceneGraph` classes to improve node management and serialization.
Changed the `EntityManager` class to enhance entity management with new component handling methods.
Added new test classes, `EntityTest` and `SerializationTest`, to ensure reliability in entity and serialization systems.
Added the `Ghost.App` project file to establish a modular project structure.
Added the `Ghost.Generator` project for automated component serialization code generation.
Updated UI components to reflect the new namespace for proper functionality.

Ghost.InternalEditor/Controls/BasicInput/PropertyField.cs

@@ -0,0 +1,24 @@
+using Microsoft.UI.Xaml;
+using Microsoft.UI.Xaml.Controls;
+
+namespace Ghost.Editor.Controls;
+
+public sealed partial class PropertyField : ContentControl
+{
+    public string Label
+    {
+        get => (string)GetValue(LabelProperty);
+        set => SetValue(LabelProperty, value);
+    }
+
+    public static readonly DependencyProperty LabelProperty = DependencyProperty.Register(
+        nameof(Label),
+        typeof(string),
+        typeof(PropertyField),
+        new PropertyMetadata(default(string)));
+
+    public PropertyField()
+    {
+        DefaultStyleKey = typeof(PropertyField);
+    }
+}

Ghost.InternalEditor/Controls/BasicInput/PropertyField.xaml

@@ -0,0 +1,33 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<ResourceDictionary
+    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+    xmlns:local="using:Ghost.Editor.Controls">
+
+    <Style TargetType="local:PropertyField">
+        <Setter Property="Template">
+            <Setter.Value>
+                <ControlTemplate TargetType="local:PropertyField">
+                    <Grid Height="32" Margin="2,4">
+                        <Grid.ColumnDefinitions>
+                            <ColumnDefinition Width="125" />
+                            <ColumnDefinition Width="*" />
+                        </Grid.ColumnDefinitions>
+                        <TextBlock
+                            Grid.Column="0"
+                            Margin="0,0,0,4"
+                            VerticalAlignment="Center"
+                            Style="{StaticResource BodyTextBlockStyle}"
+                            Text="{TemplateBinding Label}"
+                            TextTrimming="CharacterEllipsis" />
+
+                        <ContentPresenter
+                            Grid.Column="1"
+                            Content="{TemplateBinding Content}"
+                            ContentTemplate="{TemplateBinding ContentTemplate}" />
+                    </Grid>
+                </ControlTemplate>
+            </Setter.Value>
+        </Setter>
+    </Style>
+</ResourceDictionary>