Created API Controllers (#1)

Removed strongly typed inventory objects

Added EAV inventory types

Added EAV object handling philosophy

Added controllers

Added EF Core migration integration

Reviewed-on: #1

WyvernInventory.Core/Models/InventoryItemDto.cs

@@ -0,0 +1,9 @@
+namespace WyvernInventory.Core.Models;
+
+public record InventoryItemDto
+{
+    public int Id { get; set; }
+    public string Name { get; set; } = "";
+    public InventoryTypeDto Type { get; set; }
+    public List<InventoryAttributeValueDto> AttributeValues { get; set; } = [];
+}