Panel: Panel should not pop up after closing the last file if it has been hidden

[DavisVaughan]

I've been battling an issue for awhile where the Panel aggressively pops itself up at hard to determine times. I hit this a lot because I actually move everything out of the Panel and want it to be hidden for all eternity.

I've finally found a reproducible example!

• Open a file
• Send the Panel away with Cmd + J (notice it doesn't show up in minimized form at the bottom)
• Close that last file
• Notice that the Panel pops back up (shakes fist angrily at this)
• Open that file again
• Note that the Panel is now in "minimized" form at the bottom. I really don't want this! I want it to be gone!

Note that this does not happen in VS Code. It is specific to our custom behavior with the "minimized" Panel.

Screen.Recording.2024-09-19.at.1.38.35.PM.mov