[AC-1923] Add endpoint to create client organization (#3977)

* Add new endpoint for creating client organizations in consolidated billing

* Create empty org and then assign seats for code re-use

* Fixes made from debugging client side

* few more small fixes

* Vincent's feedback

src/Api/Billing/Models/Requests/CreateClientOrganizationRequestBody.cs

@@ -0,0 +1,29 @@
+using System.ComponentModel.DataAnnotations;
+using Bit.Api.Utilities;
+using Bit.Core.Enums;
+
+namespace Bit.Api.Billing.Models.Requests;
+
+public class CreateClientOrganizationRequestBody
+{
+    [Required(ErrorMessage = "'name' must be provided")]
+    public string Name { get; set; }
+
+    [Required(ErrorMessage = "'ownerEmail' must be provided")]
+    public string OwnerEmail { get; set; }
+
+    [EnumMatches<PlanType>(PlanType.TeamsMonthly, PlanType.EnterpriseMonthly, ErrorMessage = "'planType' must be Teams (Monthly) or Enterprise (Monthly)")]
+    public PlanType PlanType { get; set; }
+
+    [Range(1, int.MaxValue, ErrorMessage = "'seats' must be greater than 0")]
+    public int Seats { get; set; }
+
+    [Required(ErrorMessage = "'key' must be provided")]
+    public string Key { get; set; }
+
+    [Required(ErrorMessage = "'keyPair' must be provided")]
+    public KeyPairRequestBody KeyPair { get; set; }
+
+    [Required(ErrorMessage = "'collectionName' must be provided")]
+    public string CollectionName { get; set; }
+}