feat: capture and display the quickemu version

[flexiondotorg]

I confirm this feature has not been previously requested

• I have searched the issues and this feature has not previously been requested

Is your feature request related to a problem? Please describe.

Capture the quickemu version and display it in the popout menu. Being able to reference the Quickemu version in the Quickgui code will also be helpful for conditional logic, such as what kill strategy to use for stopping VMs as Quickemu has a working --kill action since 4.9.6.

Describe the solution you'd like

• Capture the Quickemu version via quickemu --version when Quickgui starts and store it as a float in the application state.
• Display the version of Quickemu in the popout menu under the Quickgui version in a smaller font.

Describe alternatives you've considered

None.

Additional context

None.