Add entity framework (#11)

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

src/GameIdeas/GameIdeas.Shared/Model/GamePlatform.cs

@@ -0,0 +1,11 @@
+namespace GameIdeas.Shared.Model;
+
+public partial class GamePlatform
+{
+    public int GameId { get; set; }
+    public int PlatformId { get; set; }
+    public string? Url { get; set; }
+
+    public virtual Game Game { get; set; } = null!;
+    public virtual Platform Platform { get; set; } = null!;
+}