Got the new ui flow working and the models updated. Need to get changes written to the database.

OpenArchival.DataAccess/Migrations/20250806174205_NullableParentArtifactEntryId.cs

@@ -0,0 +1,59 @@
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+namespace OpenArchival.DataAccess.Migrations
+{
+    /// <inheritdoc />
+    public partial class NullableParentArtifactEntryId : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropForeignKey(
+                name: "FK_ArtifactFilePaths_ArtifactEntries_ParentArtifactEntryId",
+                table: "ArtifactFilePaths");
+
+            migrationBuilder.AlterColumn<int>(
+                name: "ParentArtifactEntryId",
+                table: "ArtifactFilePaths",
+                type: "integer",
+                nullable: true,
+                oldClrType: typeof(int),
+                oldType: "integer");
+
+            migrationBuilder.AddForeignKey(
+                name: "FK_ArtifactFilePaths_ArtifactEntries_ParentArtifactEntryId",
+                table: "ArtifactFilePaths",
+                column: "ParentArtifactEntryId",
+                principalTable: "ArtifactEntries",
+                principalColumn: "Id");
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropForeignKey(
+                name: "FK_ArtifactFilePaths_ArtifactEntries_ParentArtifactEntryId",
+                table: "ArtifactFilePaths");
+
+            migrationBuilder.AlterColumn<int>(
+                name: "ParentArtifactEntryId",
+                table: "ArtifactFilePaths",
+                type: "integer",
+                nullable: false,
+                defaultValue: 0,
+                oldClrType: typeof(int),
+                oldType: "integer",
+                oldNullable: true);
+
+            migrationBuilder.AddForeignKey(
+                name: "FK_ArtifactFilePaths_ArtifactEntries_ParentArtifactEntryId",
+                table: "ArtifactFilePaths",
+                column: "ParentArtifactEntryId",
+                principalTable: "ArtifactEntries",
+                principalColumn: "Id",
+                onDelete: ReferentialAction.Cascade);
+        }
+    }
+}