Resize `half` window size

[kleutzinger]

Is your feature request related to a problem? Please describe.

• I prefer the half view for my most common use cases. but for the file tree, the left hand side doesn't need to be that wide.
• I have this in my config

gui:
  windowSize: "half"

Describe the solution you'd like

• It'd be nice to have a configurable value to set the width of the half.
• there already exists sidePanelWidth: 0.3333 # number from 0 to 1, but this is not respected by the half screen, only the normal screen.
• maybe something like halfSidePanelWidth: ...

Describe alternatives you've considered Staying in normal mode and resizing the left hand side via the sidePanelWidth option. But i prefer half

Additional context

• related issue: https://github.com/jesseduffield/lazygit/issues/2571

• I'd like to be able to resize the right pane to the size of the red box.

[mark2185]

Would you be interested in opening a PR? This seems like a good first issue.

It's okay if you're not interested :)

[kleutzinger]

i can give it a shot

[kleutzinger]

i couldn't figure out how to implement this myself.

[jesseduffield]

We should have four window sizes:

• normal
• tall
• half
• full

I still like having half for when you actually do want to see a little more of a window horizontally without taking up the full size.