Dependency `proton-vpn-daemon` not listed in build scripts or `setup.py`

[antermin]

Problem

When the Proton VPN GUI app is launched without proton-vpn-daemon installed, a warning is displayed in the console. However, this dependency is not declared in the package's build script (setup.py) or distribution-specific build files (DEB/RPM).

Current Behavior

• The GUI app issues a warning when proton-vpn-daemon is unavailable:

• python-proton-vpn-api-core/proton/vpn/split_tunneling/interface.py

  Line 52 in 3615c9f

  logger.warning("Split tunneling backend not found")

• The daemon is listed as a dependency only for proton-vpn-cli (GUI-only users likely do not have proton-vpn-cli installed)
• The daemon was added as a development dependency, then removed entirely with no explanation
• Neither the DEB nor RPM build scripts include proton-vpn-daemon

Evidence

The Arch Linux community identified this gap and added proton-vpn-daemon as a dependency in their build script.

Recommendation

If proton-vpn-daemon is required for split-tunneling functionality (a paid feature), declare it as an optional dependency.