showkey retrieves binding for exact string instead of key combination

Description of the problem or steps to reproduce

I think an example will explain the problem pretty well:

> showkey Ctrl-V
Ctrl-V has no binding
> showkey CtrlV
CtrlV has no binding
> showkey ctrl-v
ctrl-v has no binding
> showkey ctrlV
ctrlV has no binding
> showkey C-V
C-V has no binding
> showkey Ctrl-v
Paste

What I would expect from > showkey is that it would tell me what a particular key combination is bound to. What actually happens is, if I don't guess the exact key string (so about 80% of the time), > showkey says there is no binding, despite that key combination actually being bound. This means I have to try at least 6 different strings for each key combination I want to query, and even then I'm not entirely sure if they key is actually unbound.

As an additional observation, I can type anything into the command, like > showkey as8df7asf4, and it will reply that as8df7asf4 has no binding, without checking if that's a recognised key combination. By itself that's of course benign, but it might help illustrate the underlying problem.

Specifications

Version: 2.0.6
Commit hash: 60846f5
Compiled on July 03, 2020
OS: Manjaro KDE
Terminal: Konsole

Start by reproducing the showkey Ctrl-V and showkey Ctrl-v examples from the issue, then trace the showkey command's key-binding lookup and how it handles unrecognized strings. Done means equivalent key-combination spellings resolve to the same binding, while unknown input is distinguished from an unbound recognized key.