Refactored `DocumentReceivedNotification` to use new properties `Origin`, `EnvelopeUuid`, and `ReceiverSignature` for constructing `EnvelopeURL`. Updated `LinkToDocument` and `LinkToDocumentText` to derive from `EnvelopeURL`.
Simplified `CreateEnvelopeCommandHandler` with record-like syntax, removing private fields and directly injecting dependencies.
Renamed and refactored `QueueInvitationEmailsAsync` to `SendInvitationEmailsAsync`, using `EnvNtfService.Notify` for email notifications, centralizing logic and improving clarity.
Improved error handling in email sending with logging. Updated variable names for clarity and cleaned up `using` directives.
Introduced `EnvelopeNotificationBase` as a new base class for notifications, providing a unified structure with an abstract `GetTemplateType` method and optional attachments. Added `DocumentReceivedNotification` and updated `DocumentSignedNotification` to inherit from this base class, streamlining attachment handling and template type determination.
Refactored `IEnvelopeNotificationService` to use a generic `Notify` method, allowing for flexibility with different notification types. Updated `FinalizeEnvelopeCommandHandler` to align with the new attachment handling.
Added `EnvelopeNotificationExtensions` for converting attachments to `EmailAttachmentDto` objects and introduced `ReplacePlaceholderExtensions` for dynamic placeholder replacement in email templates using reflection. Removed outdated placeholder logic from `EnvelopeNotificationService`.
