Move splits up down left or right (swap splits)

[edrozenberg]

In certain scenarios it would be nice to be able to change/swap positions of split contents within a window/tab.

For ex. a window split with an editor on the left and shell on the right. Using a keyboard binding, the user would be able to move the left split (active/focused) to the right, and cause the right split to move to the left. Now the shell is on the left and the editor on the right.

What if there's a more complex mix of h and v splits for ex:

┌─────────────┬─────────────────┐
│             │                 │
│             ↔                 │
│             │                 │
│             ├──↕──┬───────────┤
│             │     │           │
│   Active/   │     │           │
│   Focused   │     │           │
│             │     │           │
│             │     │           │
│             │     │           │
│             │     │           │
│             │     │           │
└─────────────┴─────┴───────────┘

In this case, moving the leftmost (active) split to the right would swap its position with the topmost split immediately to the right of it (always favor the top split in case of ambiguity). If the user wants something different they can instead make some other split on the right side active, and move that smaller split in whichever direction they would like.

In the case of ambiguity when moving up or down, favor the leftmost split because Ghostty is LTR ATM :).

Swapping splits does not change the position of any of the split dividers. Only the contents of the splits are swapped, leaving the split layout unchanged. If the user wants to change the split divider positions they can do that separately if needed using existing functionality.

Edit -
I should have searched first, #3325