Copy in/out values

[janis-ab]

Problem Statement
It is impossible (or i could not find a way) to copy values in/out of calculator to/from other applications.

Evidence or User Insights
I personally often copy values in/out from calculator applications. I.e. copy in hex value, unset some bit-flags and copy out resulting value, copy in decimal value then copy out hex value, etc.

It is cumbersome and error prone to write large numbers by hand, just to copy in/out.

Tested that this is not possible to be done on https://calculator.platform.uno/ nor on local installation on current Ubuntu distribution.

Proposal
Allow Ctrl+C key binding to copy values in clipboard. Or allow context menu on right mouse click, to allow native text copying from web browser.

Goals
Improved productivity, less errors due to typos.