VNote: Argument injection to arbitrary command execution via crafted note filename in external-program handling

VNote is a note-taking platform. Prior to 4.3.0, SessionConfig::ExternalProgram::fetchCommand wraps a note path in double quotes and substitutes it into a command string that QProcess::start(const QString&) reparses into arguments through ProcessUtils::startDetached. The automatic path in src/controllers/viewareacontroller.cpp and the Open With path in src/controllers/notebooknodecontroller.cpp both reach this sink. On Linux and macOS, an attacker-controlled double quote in a POSIX note filename can terminate the quoted path and add arguments to the victim's configured external program. If the configured program supports an argument that executes commands, such as the vim or gvim -c option, the injected arguments can execute arbitrary commands as the user. This issue is fixed in version 4.3.0.