Refactored the signature handling process by introducing a new
`Report` instance creation step in the `SignatureApplied` block
to streamline signed report generation. Added a validation check
in `ExportSignedPdfAsync` to ensure the `Report` object is not
null before proceeding with export. Removed redundant code for
manual signed report creation and simplified the export logic
by directly invoking `reportViewer!.ExportToAsync`. Incremented
`ViewerKey` to refresh the report viewer after signing.
TekH
697f85f805