Checkout v2: Play sound when invoice is paid (#5113)

* Checkout v2: Play sound when invoice is paid

Closes #5085.

* Refactoring: Use low-level audio API to play the sound

Allows to play the sound regardless of browser permissions.

* Add audio file detection

* Use model state for file upload errors

* Add default sound and customizing option

* Fix mp3 detection

* Add sounds

* Update defaults

* Add nfcread and error sounds

* Improve label wording

* Replace sound

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Co-authored-by: nicolas.dorier <nicolas.dorier@gmail.com>

BTCPayServer/Models/StoreViewModels/CheckoutAppearanceViewModel.cs

@@ -3,6 +3,7 @@ using System.Collections.Generic;
 using System.ComponentModel.DataAnnotations;
 using System.Linq;
 using BTCPayServer.Services;
+using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.Mvc.Rendering;
 using Newtonsoft.Json.Linq;
 
@@ -44,6 +45,9 @@ namespace BTCPayServer.Models.StoreViewModels
         [Display(Name = "Celebrate payment with confetti")]
         public bool CelebratePayment { get; set; }
 
+        [Display(Name = "Enable sounds on checkout page")]
+        public bool PlaySoundOnPayment { get; set; }
+
         [Display(Name = "Requires a refund email")]
         public bool RequiresRefundEmail { get; set; }
 
@@ -61,9 +65,14 @@ namespace BTCPayServer.Models.StoreViewModels
 
         [Display(Name = "Link to a custom CSS stylesheet")]
         public string CustomCSS { get; set; }
+        
         [Display(Name = "Link to a custom logo")]
         public string CustomLogo { get; set; }
 
+        [Display(Name = "Custom sound file for successful payment")]
+        public IFormFile SoundFile { get; set; }
+        public string SoundFileId { get; set; }
+
         [Display(Name = "Custom HTML title to display on Checkout page")]
         public string HtmlTitle { get; set; }