- build: add app icon for macOS and Windows
- ui: add header with logo + app smoke test
- add ad-hoc codesign to macOS builds to prevent Gatekeeper 'damaged' error
- split release workflow into bump.yml + release.yml
- replace GNU timeout with portable bash pattern for macOS smoke test
- skip numba on macOS Intel (no llvmlite wheel for py3.13 x86_64)
- replace deprecated macos-13 runner with macos-15-intel for Intel x64 builds