[feat] Add `leftsuper` and `rightsuper` Keys

[trueNAHO]

Motivation

Towards a more ergonomic working environment. This PR enables the use of the super key as a keysym.

Help Needed

All tests successfully pass:

$ make test
test result: ok. 51 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.04s

     Running unittests src/main.rs (target/debug/deps/swhks-328709fb84de0909)

running 0 tests

test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s

However, the added unit test does not seem to work as expected when added to $HOME/.config/swhkd/swhkdrc:

leftsuper
    konsole

rightsuper
    qutebrowser

Possibly, the key listener is unable to distinguish between config::Modifier::Super and Key::KEY_LEFTMETA or Key::KEY_RIGHTMETA key presses because both Key::KEY_LEFTMETA and Key::KEY_RIGHTMETA keys are mapped to the same config::Modifier::Super modifier:

let modifiers_map: HashMap<Key, config::Modifier> = HashMap::from([
    (Key::KEY_LEFTMETA, config::Modifier::Super),
    (Key::KEY_RIGHTMETA, config::Modifier::Super),
]);

Since I am unfamiliar with Rust, I believe it would be appropriate for someone with Rust experience to handle this situation.

Closes Issue

• https://github.com/waycrate/swhkd/issues/209

Related Issues

• https://github.com/waycrate/swhkd/issues/103
• https://github.com/waycrate/swhkd/issues/211

Heavily Inspired By

• https://github.com/waycrate/swhkd/pull/213

[obvionaoe]

What's blocking this PR?

[Shinyzenith]

I believe this pr is incomplete if memory serves me correctly.

[Shinyzenith]

Feel free to finish up on the work

[trueNAHO]

Apologies for the confusion and delay in my response. This PR was meant as a starting point, but I can't finish it myself:

Since I am unfamiliar with Rust, I believe it would be appropriate for someone with Rust experience to handle this situation.

I should have opened an issue instead of submitting an incomplete PR. Feel free to take over and initiate a new one.