Add entity framework (#11)

Co-authored-by: Maxime Adler <madler@sqli.com>
Reviewed-on: #11

src/GameIdeas/GameIdeas.Shared/Model/GameDeveloper.cs

@@ -0,0 +1,10 @@
+namespace GameIdeas.Shared.Model;
+
+public partial class GameDeveloper
+{
+    public int GameId { get; set; }
+    public int DeveloperId { get; set; }
+
+    public virtual Game Game { get; set; } = null!;
+    public virtual Developer Developer { get; set; } = null!;
+}