Use shift+k and shift+j to select prev/next of same kind

[pheki]

This would also fix jj-vcs/jj#5867

My workflow is basically:

• Unfold file (f)
• Go to first section (j / l / shift+right / shift+l)
• Review each section using Fn+Down/Fn+Up and space (this is where PageDown/PageUp are located on my keyboard)
• Go back to file (shift+h ideally, but I was using shift+right because it wasn't working, see Fix shift+h and shift+l #112)
• Fold file (f)
• Next file (j)

It's all very messy, moving the hand all the time and switching between Fn and Shift gets very confusing

With this my workflow becomes:

• Unfold file (f)
• Go to first section (j / l / shift+l)
• Review each section using shift+j/shift+k and space
• Go back to file (shift+h)
• Fold file (f)
• Next file (j)

A lot simpler! Just shift and the main keyboard keys.

I opened it separately from #112 as that one is just a bugfix, probably easier to be reviewed and merged than this one.

[emesterhazy]

This seems like a good idea to me. In fact, we should probably deprecate page up and page down and add shift up / down as well.

I think this PR needs two things before we can merge it:

1. We should update the help dialogue

   scm-record/scm-record/src/ui.rs

   Lines 3543 to 3585 in 32162a5

   	fn draw(&self, viewport: &mut Viewport<Self::Id>, _: isize, _: isize) {
   	let title = "Help";
   	let body = Text::from(vec![
   	Line::from("You can click the menus with a mouse, or use these keyboard shortcuts:"),
   	Line::from(""),
   	Line::from(vec![
   	Span::raw(" "),
   	Span::styled("General", Style::new().bold().underlined()),
   	Span::raw(" "),
   	Span::styled("Navigation", Style::new().bold().underlined()),
   	]),
   	Line::from(
   	" Quit/Cancel q Next/Prev j/k or ↓/↑",
   	),
   	Line::from(" Confirm changes c Next/Prev of same type PgDn/PgUp"),
   	Line::from(" Force quit ^c Move out & fold h or ←"),
   	Line::from(
   	" Move out & don't fold H or Shift-← ",
   	),
   	Line::from(vec![
   	Span::raw(" "),
   	Span::styled("View controls", Style::new().bold().underlined()),
   	Span::raw(" Move in & unfold l or →"),
   	]),
   	Line::from(" Expand/Collapse f"),
   	Line::from(vec![
   	Span::raw(" Expand/Collapse all F "),
   	Span::styled("Scrolling", Style::new().bold().underlined()),
   	]),
   	Line::from(" Edit commit message e Scroll up/down ^y/^e"),
   	Line::from(" or ^↑/^↓"),
   	Line::from(vec![
   	Span::raw(" "),
   	Span::styled("Selection", Style::new().bold().underlined()),
   	Span::raw(" Page up/down ^b/^f"),
   	]),
   	Line::from(
   	" Toggle current Space or ^PgUp/^PgDn",
   	),
   	Line::from(" Toggle and advance Enter Previous/Next page ^u/^d"),
   	Line::from(" Invert all a"),
   	Line::from(" Invert all uniformly A"),
   	]);

2. Update CHANGELOG.md

Let's not remove page up and page down yet, but would you also add shift up and shift down keybinds?

[pheki]

Ok, so there's a bit of a challenge here, if we just leave all 3 of them the line ends waaay too big (and if the terminal screen is too narrow for the dialog, it panics with:

thread 'main' (39737) panicked at scm-record/src/render.rs:218:10:
called `Result::unwrap()` on an `Err` value: UnsatisfiableConstraint

So I removed PgDn/PgUp from the dialog and it's smaller (although still bigger than other lines). There are alternatives, like separating next/prev (a bit less consistent with the rest of the menu), etc.

Also, I just realized, is there a reason scroll is at ^y/^e instead of ^j/^k? It would be very practical that way haha.

PS.: I had no idea there was a help dialogue, when mentioned I tried h (standard to unix utilities such as less) and had to look into the source to figure it was ?, even though I think I have seen ? in TUIs the past, just forgotten. Maybe there could be a reference to it in the menu?

[emesterhazy]

There's actually another PR open to add a Help menu item to make it easier to find the help dialogue.

I'll have to play around with this to see how easy it is to trigger a panic. Shortening the dialogue sounds reasonable to me. Maybe we should even just remove the page up / page down keybindings, but I guess we can hold off on it since we aren't planning to repurpose them.

RE: ^y/^e, I'm not sure. Something to think about for sure.