[PM-20087] [PM-21104] Preview tax amount for organization trial initiation (#5787)

* [NO LOGIC] [PM-21104] Organize Core.Billing tax code

* Add PreviewTaxAmountCommand and expose through TaxController

* Add PreviewTaxAmountCommandTests

* Run dotnet format

src/Api/Billing/Controllers/TaxController.cs

@@ -0,0 +1,36 @@
+using Bit.Api.Billing.Models.Requests;
+using Bit.Core.Billing.Tax.Commands;
+using Microsoft.AspNetCore.Authorization;
+using Microsoft.AspNetCore.Mvc;
+
+namespace Bit.Api.Billing.Controllers;
+
+[Authorize("Application")]
+[Route("tax")]
+public class TaxController(
+    IPreviewTaxAmountCommand previewTaxAmountCommand) : BaseBillingController
+{
+    [HttpPost("preview-amount/organization-trial")]
+    public async Task<IResult> PreviewTaxAmountForOrganizationTrialAsync(
+        [FromBody] PreviewTaxAmountForOrganizationTrialRequestBody requestBody)
+    {
+        var parameters = new OrganizationTrialParameters
+        {
+            PlanType = requestBody.PlanType,
+            ProductType = requestBody.ProductType,
+            TaxInformation = new OrganizationTrialParameters.TaxInformationDTO
+            {
+                Country = requestBody.TaxInformation.Country,
+                PostalCode = requestBody.TaxInformation.PostalCode,
+                TaxId = requestBody.TaxInformation.TaxId
+            }
+        };
+
+        var result = await previewTaxAmountCommand.Run(parameters);
+
+        return result.Match<IResult>(
+            taxAmount => TypedResults.Ok(new { TaxAmount = taxAmount }),
+            badRequest => Error.BadRequest(badRequest.TranslationKey),
+            unhandled => Error.ServerError(unhandled.TranslationKey));
+    }
+}