Add UI actions and handlers to mark QSLs as received or requested. Updates ui/LogbookWidget.ui to add actionQSLRcvd and actionQSLRequested and wire them into the UI. Add slot declarations in LogbookWidget.h. Implement markQslReceived() and markQslRequested() in LogbookWidget.cpp: they operate on selected rows, set QSL columns (including setting QSL received date to current date), use OnManualSubmit while updating, submit changes, restore the model's edit strategy, and refresh the table. Also add QDate include and insert a new separator into the contact table context menu.