[BUG]: Non-matching exclude pathspec causes an error in empty repository when the flag "--update" is present

I found a regression in version 2.45.0. (It's still present in the current next - 2.49.0.1266.g31b7d2e469; earlier versions work fine.)

When you run "git add --update" with an exclude pathspec on an empty repository, the command fails, showing an error about not being able to find the specified files. This happens only if the repository contains no files. Adding any files (even with "git add -N") or making a non-empty commit fixes the issue, regardless of whether the added files match the exclude pathspec or not.

Way to reproduce: git init git add --update -- ':(exclude)foo'

This results in: error: pathspec ':(exclude)foo' did not match any file(s) known to git error: pathspec '.' did not match any file(s) known to git