Add support for Apple XLIFF about weblate

[nijel]

Weblate doesn't yet support this propritetary way of storing plural, see translate/translate#4614

[github-actions]

The issue you've reported needs to be addressed in the translate-toolkit. Please file the issue there, and include links to any relevant specifications about the formats (if applicable).

[bryceco]

I understand that this is a proprietary way of handling plurals in XLIFF, and I don't expect Weblate to provide first-class support to them. But I'm still confused about why the "one" and "other" strings are displayed while "few" and "many" are not. Is this also part of translate? Because the bug reports there imply they should be present, just not recognized as plural forms. Thanks!

[nijel]

I guess you've configured it as monolingual format and in that case only keys present in the source file are shown.

[bryceco]

All 4 plurals are present in the XLIFF I'm uploading. Or maybe I misunderstand you.
Edit: Okay, I think I see what you mean. So I should be able to fix it by disabling monolingual.
Edit2: Removing the "Monolingual base language file" setting seems give me the result I wanted. Thanks @nijel!