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.Server/EnvelopeGenerator.Server.Client/Models/SignatureSubmitDto.cs

@@ -0,0 +1,10 @@
+namespace EnvelopeGenerator.Server.Client.Models;
+
+public sealed record SignatureSubmitDto
+{
+    public required int Id { get; init; }
+    public required string DataUrl { get; init; }
+    public required string FullName { get; init; }
+    public string? Position { get; init; }
+    public required string Place { get; init; }
+}