Adding of archive items is mostly operational. Need to handle file upload

OpenArchival.Core/DataObjects/ArchiveItem.cs

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+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace OpenArchival.Core;
+
+public class ArchiveItem
+{
+    public required Category Category { get; set; }
+    
+    public required string ItemTitle { get; set; }
+
+    public string? Description { get; set; }
+
+    public string? StorageLocation { get; set; }
+
+    public string? ArtifactType { get; set; }
+
+    public List<string>? Tags { get; set; }
+
+    public List<string>? ListedNames { get; set; }
+
+    public List<DateTime>? AssociatedDates { get; set; }
+
+    public List<string>? Defects { get; set; }
+
+    public List<string>? RelatedArtifacts { get; set; }
+    
+    /// <summary>
+    /// TODO: Implement
+    /// </summary>
+    public List<string>? Files { get; set; }
+
+    public bool IsPublic { get; set; } = true;
+}

OpenArchival.Core/DataObjects/Category.cs

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+using System.Runtime.CompilerServices;
+
+namespace OpenArchival.Core;
+
+public class Category
+{
+    public int CategoryId { get; set; }
+    public required string CategoryName { get; set; }
+    public required string FieldSeparator { get; set; }
+    public required string[] FieldNames { get; set; }
+    public required string[] FieldDescriptions { get; set; }
+
+    public IEnumerable<KeyValuePair<string, string>> FieldsIterator
+    {
+        get
+        {
+            for (int index = 0; index < FieldNames.Length; ++index)
+            {
+                yield return new KeyValuePair<string, string>(FieldNames[index], FieldDescriptions[index]);
+            }
+        }
+    }
+}

OpenArchival.Core/DataObjects/CategoryFieldOption.cs

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+namespace OpenArchival.Core;
+
+public class CategoryFieldOption
+{
+    public required int CategoryId { get; set; }
+    public required int FieldNumber { get; set; }
+    public required string Value { get; set; } 
+    public required string Name { get; set; }
+    public string? Description { get; set; }
+}

OpenArchival.Core/DataObjects/FileInfo.cs

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+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace OpenArchival.Database;
+
+public class FileInfo
+{
+    public int Id { get; set; }
+    public required string Filename { get; set; }
+    public required string Path { get; set; }
+}