Feature request: click and drag to resize or rearrange panes

[Jasha10]

Some tiling window managers (e.g. Pop!_OS Shell for linux or yabai for macOS) implement click-and-drag functionality for resizing or reordering windows. This creates a user experience where you can either use keyboard shortcuts to move your windows around or use the mouse. The window manager updates the tiling based on where you've dragged the window to.

I think zellij might be able to implement something similar for resizing panes and moving them around.

Here's what I'm thinking:

• click and drag a boarder between two panes to resize
• click and drag the title of a pane to "move" the pane; the location where the mouse is released would determine where the pane is moved to. For example, would could implement:
  • click and drag the pane onto a tab's label to move the pane to that tab
  • click and drag the pane onto the center of another pane to switch the spots of the two panes
  • click and drag onto another pane, near the edge of that other pane, to "split" the other pane into two parts (either vertically or horizontally). The dragged pane would then be inserted vertically or horizontally in the tiling tree as a neighbor of the other pane.

Here is an image from the yabai wiki illustrating what behaviors you get by dragging one window onto another window; the behavior differs depending on the region where the mouse drag is released: