Add key binding to toggle nick list visibility

[jeremyredhead]

Closes #5

this commit actually works perfectly now, it's only still 'WIP' so you can give case of code critiques (INB4 add_summary_bit is too DRY xD), and for discussion of the Right PBLN/summary format. but yeah! otherwise it works 100% how one would hope/expect! (well, AFAICT -- i did not e.g. test turning off internet whilst nick list collapsed...)

Thank you for all your help & advice with Rust, Garmy! :D

(and yes, no access 4 u to my branch this time >:P plz tell me how 2 fix instead 😇, and i will amend & force push myself)

[jeremyredhead]

ok wow i am just now realizing a lot of those comments in the code i should've expunged and made as comments here in the PR instead. me silly

[jeremyredhead]

OK, I updated based on your comments left in &cove, as well as running cargo fmt :P

I also decided to allow you to make edits to my branch after all, since cove is "your baby" :D

[Garmelon]

I also just remembered there is already a pbln format in cove, namely in the room list :D

[jeremyredhead]

I also just remembered there is already a pbln format in cove, namely in the room list :D

oh shiiiit, you're right. i also forgot lmao

Should the collapsed nick list use that format instead? (I'm not a big fan of "lurker" being abbreviated as 'l' (lowercase ell) tho :S)

I see that takes yet another, entirely different approach to assembly by using an array vector :D

[Garmelon]

No, I think the collapsed nick list format should look similar to the expanded nick list headings.

[jeremyredhead]

OK, I implemented the changes (more or less) from review which I agreed with or didn't care about, along with adding a note about the tricksy leading space :P, and moving let mut list_builder into the else branch -- yeah yeah, i'm sure it's optimized out by Rust compiler but uhh the moment I noticed it I was bothered :P (why am I summarizing what is already available with the Compare link? IDK, I'm Craaazzyy~)

I think "show or hide" is a little better than "collapse or expand", but meh, doesn't matter too much.

I do however still feel strongly that P1 B2 ... looks better than P(1) B(2) ... in practice, even if the latter seems intuitively/logically superior. But obviously change that if you want. Either way I think this is ready to merge. (actually, the previous iteration was too... the fact that its commit message started with "WIP:" was a mistake on my part >.>)