Refactor project layout and fetch STM32CubeF1 drivers
Move core sources to src/ and headers to include/, remove in-repo Drivers/, and add GitLab CI + CMake FetchContent to download drivers at configure time.
Made-with: Cursor
Move core sources to src/ and headers to include/, remove in-repo Drivers/, and add GitLab CI + CMake FetchContent to download drivers at configure time.
Made-with: Cursor