hide diff file header section when showing diff of file selected in Files section

[santhosh-tekuri]

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

When I select a file in Files section the diff shown in main view contains first five lines about the file header. I want an option to remove this to save five lines
and I obviously know which file I am looking at

Describe the solution you'd like

remove file header in diff when showing diff for file in Files section

Describe alternatives you've considered

none

[stefanhaller]

I might find this useful too, but there are a few questions around it.

1. Currently, when moving the selection between a folder containing a single file, and the file itself, the main view doesn't change. With this change it would, because the file headers would still have to be displayed when a folder is selected, but would disappear when you select the file; this could look jarring.
2. It would have to work when a pager is used too, because I think it's a waste to use lazygit without one. Two questions:
   a. Can all pagers cope with the header missing? The two I have just tested do, which is great (delta and diff-so-fancy), but I'm not sure that's true for all of them.
   b. I'm not sure how to implement it in this case. git diff doesn't have an option to suppress the header, and the pager is called directly by git, so there's no way for us to intercept the data to strip the header before it's passed to the pager. (I mean sure, there are ways, but they are way too much effort for this small benefit.)

So, I'd say if git one day has an option to suppress the header, I'll be happy to add support for it in lazygit. Until then, I don't see this happening.