--batch or some --paths-file for very long lists of paths

Dear Git Gurus,

In DataLad (https://datalad.org) we are doing "our own" analysis of what specific files (not entire directories) should git and git-annex operate on. Obviously, in large repositories (and we have with >100k files) that might require invoking git add or git diff etc with a long list of paths specified in the command line. For that we often split invocation into multiple and even resort to git commit --amend to combine multiple commits then into a single one.

But I wondered if may be there is already some trick to make such commands as status, diff, add, commit to operate on arbitrarily long list of paths passed to that git command somehow.

Note that gitglossary (at least in 2.35.1 git on debian) says that 

	Pathspecs are used on the command line of "git ls-files", "git
    ls-tree", "git add", "git grep", "git diff", "git checkout", and many other
    commands ...

but 

	$> git ls-tree -h | head -n1
	usage: git ls-tree [<options>] <tree-ish> [<path>...]

so it is <path> not the <pathspec> like (why in stderr this time?)

	$> git commit -h 2>&1 | head -n1
	usage: git commit [<options>] [--] <pathspec>...

So if in both cases it is pathspec, may be pathspec could support some other magical keyword like :(filelist)/tmp/mylonglistofpaths ?

Thanks in advance for your time and thoughts,