Fixes:
- Fix build for Alpine Linux and BSD
- Fix integration with internal Qt toolbar visibility state
- Fix plugin search (regression from 2.4.2)
- Fix several Windows UTF-16 issues
Build related changes:
- Add -fno-gnu-unique to default build flags
- Implement VERBOSE make flag
- Make build compatible with LTO, now enabled on official macOS/Windows binaries
- Replace CARLA_EXPORT macro with separate API / PLUGIN export options
- Set new X-NSM-Exec desktop file property