Flutter integration:
- Update SingboxConfigOption with per-app proxy fields
- Add perAppProxyMode, includedApplications, excludedApplications
- Read per-app settings from SharedPreferences
- Pass settings to libcore via HiddifyOptions
libcore backend:
- Implement ProcessName routing rules for desktop platforms
- Support include mode (whitelist) and exclude mode (blacklist)
- Only Chrome/Firefox/etc. specified by name use VPN
Version bump: 1.7.5 → 1.7.6
Update libcore submodule to include per-app proxy support