Layout flashing when use custom command

[xzbdmw]

Describe the bug
as title

To Reproduce
config:

# Config relating to the Lazygit UI
gui:
    # Number from 0 to 1.0.
    sidePanelWidth: 0.33
    # If true, increase the height of the focused side window; creating an accordion effect.
    expandFocusedSidePanel: false
    showBottomLine: false
customCommands:
  - key: <c-o>
    command: 'echo "hello"'
    context: "files"

press <c-o>, layout changes as if expandFocusedSidePanel and showBottomLine are both true for a very brief moment.

Expected behavior
no flashing

iShot_2025-01-21_07.28.39.mp4

Screenshots
If applicable, add screenshots to help explain your problem.
wrong moment：

Version info:
Latest main

Additional context
Add any other context about the problem here.

Note: please try updating to the latest version or manually building the latest master to see if the issue still occurs.

[jesseduffield]

The bottom line will appear whenever an action is pending, to show you a loading status. That causes the rest of the layout to be briefly affected. Not sure what a good solution is for that. Perhaps just showing the loading state on the bottom border of the stash view so that the layout doesn't need to change.

[xzbdmw]

Hmm, what if the border of stash can't fit in the loading status?

[jesseduffield]

I'm talking more generally about the bottom frames of any view on the bottom, so it would always fit