Add routes for receiver-ui and register SignatureService

Expanded `yarp.json` with new routes for the `receiver-ui` cluster to handle paths for `appsettings.json`, `appsettings.Development.json`, styles, fonts, and images. These routes specify HTTP methods and execution order.

Registered `SignatureService` as a scoped dependency in `Program.cs` to support new functionality related to handling signatures.

EnvelopeGenerator.API/yarp.json

@@ -90,6 +90,46 @@
         "Methods": [ "GET", "HEAD" ]
       }
     },
+    "receiver-ui-appsettings": {
+      "ClusterId": "receiver-ui",
+      "Order": 50,
+      "Match": {
+        "Path": "/appsettings.json",
+        "Methods": [ "GET", "HEAD" ]
+      }
+    },
+    "receiver-ui-appsettings-dev": {
+      "ClusterId": "receiver-ui",
+      "Order": 50,
+      "Match": {
+        "Path": "/appsettings.Development.json",
+        "Methods": [ "GET", "HEAD" ]
+      }
+    },
+    "receiver-ui-styles": {
+      "ClusterId": "receiver-ui",
+      "Order": 50,
+      "Match": {
+        "Path": "/EnvelopeGenerator.ReceiverUI.styles.css",
+        "Methods": [ "GET", "HEAD" ]
+      }
+    },
+    "receiver-ui-fonts": {
+      "ClusterId": "receiver-ui",
+      "Order": 200,
+      "Match": {
+        "Path": "/fonts/{**catch-all}",
+        "Methods": [ "GET", "HEAD" ]
+      }
+    },
+    "receiver-ui-images": {
+      "ClusterId": "receiver-ui",
+      "Order": 200,
+      "Match": {
+        "Path": "/images/{**catch-all}",
+        "Methods": [ "GET", "HEAD" ]
+      }
+    },
     "auth-login": {
       "ClusterId": "auth-hub",
       "Match": {

EnvelopeGenerator.ReceiverUI/Program.cs

@@ -20,6 +20,7 @@ builder.Services.AddScoped<EnvelopeGenerator.ReceiverUI.Services.DocumentService
 builder.Services.AddScoped<EnvelopeGenerator.ReceiverUI.Services.AuthService>();
 builder.Services.AddScoped<EnvelopeGenerator.ReceiverUI.Services.AnnotationService>();
 builder.Services.AddScoped<EnvelopeGenerator.ReceiverUI.Services.EnvelopeReceiverService>();
+builder.Services.AddScoped<EnvelopeGenerator.ReceiverUI.Services.SignatureService>();
 
 builder.Services.AddDevExpressWebAssemblyBlazorReportViewer();
 builder.Services.AddDevExpressWebAssemblyBlazorPdfViewer();