Addition of support for the Kitty keyboard protocol.

[cxreiff]

Changes

• Supplies enable_kitty_protocol method that uses crossterm helper methods to enable the Kitty keyboard protocol.
• Cleans up kitty protocol flags when leaving ratatui alternate view.
• New example showing how to use the method and one example of what it supplies (keyboard "release" events).
• EDIT: Also added the cursor::Show during cleanup, necessary in some terminals.

Justification

One could argue that kitty protocol support is somewhat orthogonal to what an integration between bevy and ratatui should be responsible for, but I think there are two good arguments for inclusion:

• Bevy users will be accustomed to more keyboard events than terminals supply by default, and especially if the eventual plan is to convert crossterm events into the standard bevy ones, this protocol will be required for better parity.
• If the kitty protocol flags are pushed before the ratatui alternate view is created it can cause issues with using the protocol (or if the alternate view is exited before the flags are removed the terminal might not be left in the proper state). For this reason, handling the protocol here might cause less user frustration than pointing them elsewhere or making them add the flags themselves.

Alternative

Alternatively, for an even more seamless setup we could just push the flags as part of the context initialization and store whether the protocol was enabled as part of the RatatuiContext struct. Opinion here?

Testing

Tested with Alacritty, Kitty, iTerm, and WezTerm on macOS.

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 0% with 17 lines in your changes missing coverage. Please review.

Project coverage is 0.00%. Comparing base (0e57e80) to head (f2bd462).

Files	Patch %	Lines
src/terminal.rs	0.00%	12 Missing ⚠️
src/event.rs	0.00%	5 Missing ⚠️

Additional details and impacted files

@@          Coverage Diff          @@
##            main      #5   +/-   ##
=====================================
  Coverage   0.00%   0.00%           
=====================================
  Files          4       4           
  Lines        116     129   +13     
=====================================
- Misses       116     129   +13     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[joshka]

EDIT: Also added the cursor::Show during cleanup, necessary in some terminals.

In theory that's handled by Terminal::drop - https://github.com/ratatui-org/ratatui/blob/main/src/terminal/terminal.rs#L91-L95, but I suppose that it likely suffers the same problems that happen when panics happen (maybe - I don't 100% recall if drop gets skipped). There was some discussion on a bevy issue about adding a shutdown / teardown system similar to the way the startup systems run, but it petered out due to lack of interest. I was thinking that this might be a good reason to go back to that idea.

One could argue that kitty protocol support is somewhat orthogonal to what an integration between bevy and ratatui should be responsible for, but I think there are two good arguments for inclusion:

I had a vague thought that perhaps it's worth splitting bevy_ratatui and bevy_crossterm perhaps, but for now it's useful to think of them as paired (and there's an existing https://crates.io/crates/bevy_crossterm that seems to be abandoned - it uses a custom runner approach rather than just using the existing systems / schedules like I have).

For now, I'm fine with keeping this sort of thing in the lib, then we can work out where it goes when evolving. (get it working, get it right, get it performing)

Bevy users will be accustomed to more keyboard events than terminals supply by default, and especially if the eventual plan is to convert crossterm events into the standard bevy ones, this protocol will be required for better parity.

Yup - I want that - you're thinking the same thing as me there.

Alternatively, for an even more seamless setup we could just push the flags as part of the context initialization and store whether the protocol was enabled as part of the RatatuiContext struct. Opinion here?

I'll think about this as I look through the code. I ran into a similar problem with mouse capture implementing the crossterm / mouse events earlier today.

[joshka]

LGTM

[cxreiff]

Thank you for fixing that up!