Add desktop launcher with account and VPN management
Provide a GTK interface with VTE terminal tabs, saved environment actions, stop-all control, a tray menu, desktop integration and optional autostart. Unify form sizing and spacing, and fix application and terminal lifecycles.
Support multiple accounts per agent, account login from settings, editable and removable VPN profiles, Hiddify VLESS links and Russian profile names. Rename the default connection to VPN хоста while preserving the none ID; host VPN bypass is not implemented.
Add the version 0.8.2 Debian package builder, installation documentation, and desktop, packaging, account and VPN regression coverage.
Validation: 170 tests passed, plus 3 GUI layout checks at 200% scale with 144 DPI fonts. Staged changes pass git diff --check.