Updated the Signature Certificate report to display the correct
label "Read and confirmed" for "Read and Sign" envelopes.
- Added `DocumentSignedRaC` resource key to `Model.resx` and
`Model.en.resx` with localized values ("Gelesen und bestätigt"
and "Read and confirmed").
- Updated `ReportItem.vb` to include conditional logic in
`ItemStatusTranslated` for "Read and Sign" envelopes.
- Added strongly-typed property for `DocumentSignedRaC` in
`Model.Designer.cs`.
- Updated `fix-report-label-read-and-confirmed.md` documentation
to reflect changes, including testing steps and task completion.
These changes ensure accurate status labels in the report for
different envelope types.