Move version.go from src/core to src/app to prepare for deleting the
now-empty src/core package. Update all imports and build script
references to use src/app.Version instead of src/core.Version.
Fix import aliasing conflict between Fyne's desktop package and our
platform/desktop package by aliasing Fyne imports as fyneapp and
fynedesktop.
Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>
mixeme
2f5c920c3e