Feature/use hcaptcha if bot (#1476)

* Add captcha to login models and methods

* Add captcha web auth to login

* Extract captcha to abstract base class

* Add Captcha to register

* Null out captcha token after each successful challenge

* Cancel > close

src/Core/Models/Request/RegisterRequest.cs

@@ -15,5 +15,6 @@ namespace Bit.Core.Models.Request
         public Guid? OrganizationUserId { get; set; }
         public KdfType? Kdf { get; set; }
         public int? KdfIterations { get; set; }
+        public string CaptchaResponse { get; set; }
     }
 }

src/Core/Models/Request/TokenRequest.cs

@@ -16,10 +16,11 @@ namespace Bit.Core.Models.Request
         public string Token { get; set; }
         public TwoFactorProviderType? Provider { get; set; }
         public bool? Remember { get; set; }
+        public string CaptchaToken { get; set; }
         public DeviceRequest Device { get; set; }
 
         public TokenRequest(string[] credentials, string[] codes, TwoFactorProviderType? provider, string token,
-            bool? remember, DeviceRequest device = null)
+            bool? remember, string captchaToken, DeviceRequest device = null)
         {
             if (credentials != null && credentials.Length > 1)
             {
@@ -36,6 +37,7 @@ namespace Bit.Core.Models.Request
             Provider = provider;
             Remember = remember;
             Device = device;
+            CaptchaToken = captchaToken;
         }
 
         public Dictionary<string, string> ToIdentityToken(string clientId)
@@ -77,6 +79,11 @@ namespace Bit.Core.Models.Request
                 obj.Add("twoFactorProvider", ((int)Provider.Value).ToString());
                 obj.Add("twoFactorRemember", Remember.GetValueOrDefault() ? "1" : "0");
             }
+            if (CaptchaToken != null)
+            {
+                obj.Add("captchaResponse", CaptchaToken);
+            }
+
             return obj;
         }