The MessageSystem is based on Subject instead of Content (just semantics)

src/Web/Migrations/20240707023204_UseSubjectId_InsteadOfContentId.cs

@@ -0,0 +1,22 @@
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+namespace Hutopy.Web.Migrations
+{
+    /// <inheritdoc />
+    public partial class UseSubjectId_InsteadOfContentId : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+
+        }
+    }
+}