Introduce a new DXCCSubmissionDialog (ui/DXCCSubmissionDialog.{h,cpp,ui}) to generate DXCC submission lists and export them as ADIF. The dialog supports entity- or band-scoped views (including 5-band and custom band selections), mode filters, confirmation filters (LoTW / paper), and status filters (not submitted / submitted / granted).

SQL logic includes a slot_credits CTE to correctly aggregate credit_submitted/credit_granted across all QSOs per slot (fixes incorrect status when the displayed QSO differs from credited QSOs). Integrates dynamic band checkbox generation from BandPlan and adds export ADIF functionality via ExportDialog.

Project integration: QLog.pro updated to include the new sources/headers/forms, and MainWindow.{cpp,h,ui} updated to add a menu action and showDXCCSubmission() to open the dialog.