diff kitten feature enhancements for terminal power users

[razcore-rad]

Is your feature request related to a problem? Please describe.
What stops the diff kitten being a useful tool in my opinion are these two lacking features:

1. Select and transfer hunks from one file to the other.
2. When running on directories it should present a browser so we can select which files to open instead of diffing one-by-one.

Describe the solution you'd like
For 1. - be able to select hunks with the keyboard and transfer them to the other file, similar to how hints work. For example we could have ctrl+shift+p>k to bring up the interface for selecting a hunk with the numbering/lettering system. Then if the hunk does exist in one file and not the other it should be copied over. Maybe a ctrl+shift+p>d for deleting hunks. I'm sure we can come up with a reasonable behavior. We also need some undo/redo or cancel operation somehow.

For 2. - something like a dual panel similar to meld would be nice where files that have differences are color-coded, then we should be able to select which file we want to open in the per-file diff view.

Describe alternatives you've considered
Replace using the diff kitten with meld which is a GUI app, I'd rather stay in kitty if possible.

Additional context
Example meld selection panel for directory diff:

Example meld transferring from one file to the other in per-file diff view:

[kovidgoyal]

The diff kitten is exactly that, diff. Patchset management features are
out of scope for it.