- .gitmodules: Set submodule branch to feature/qt6-migration-basis-modules
- app/Dockerfile: Update FROM ubuntu:24.04 to ubuntu:26.04
- files/qt6-submodule-migration-changes.md: Update status with successful test results
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Entire-Checkpoint: 01M08CV4EFR0GM7NSVCTBC16K5