Add signature submission feature and pipeline updates

Introduced a new feature for submitting signatures, including
backend and frontend changes. Added `SignatureSubmitDto` and
`SubmitAsync` in `SignatureService` to handle signature data
submission. Implemented a new `Submit` endpoint in
`SignatureController` to validate and process signature payloads.

Updated pipeline behaviors to include `SaveSignatureBehavior`
and adjusted the execution order. Enhanced query logic in
`EnvelopeReceiverResolutionBehavior` and `SaveSignatureBehavior`
to align with the updated data model.

Refactored `EGDbContext` to improve trigger handling and logging.
Updated `ReceiverSignedPage.razor` to integrate `SignatureService`
and handle submission errors gracefully. Adjusted application
URLs in `launchSettings.json` and added new database triggers
in `appsettings.json`.

EnvelopeGenerator.Application/DependencyInjection.cs

@@ -65,18 +65,21 @@ public static class DependencyInjection
             cfg.AddBehavior<IPipelineBehavior<SigningCommand, Unit>, EnvelopeReceiverResolutionBehavior>();
             
             // 1. AnnotationBehavior - Saves annotations (executes second)
+            cfg.AddBehavior<IPipelineBehavior<SigningCommand, Unit>, SaveSignatureBehavior>();
+
+            // 2. AnnotationBehavior - Saves annotations for legacy web flow
             cfg.AddBehavior<IPipelineBehavior<SigningCommand, Unit>, AnnotationBehavior>();
             
-            // 2. DocStatusBehavior - Creates document status (executes third)
+            // 3. DocStatusBehavior - Creates document status
             cfg.AddBehavior<IPipelineBehavior<SigningCommand, Unit>, DocStatusBehavior>();
 
-            // 3. HistoryBehavior - Records history (executes fourth)
+            // 4. HistoryBehavior - Records history
             cfg.AddBehavior<IPipelineBehavior<SigningCommand, Unit>, HistoryBehavior>();
             
-            // 4. SendSignedMailBehavior - Sends notification email (executes LAST, only if all previous succeed)
+            // 5. SendSignedMailBehavior - Sends notification email (executes LAST)
             cfg.AddBehavior<IPipelineBehavior<SigningCommand, Unit>, SendSignedMailBehavior>();
         });
 
         return services;
     }
-}
+}