c++-ts-mode and namespace indentation

[Louis-Guillaume Gagnon]

Hello,

I've recently switched to the new c++-ts-mode (a game changer for source
code featuring deeply nested templates!). I'm quite pleased with it, but
I can't figure out how to make it such that a namespace block doesn't
increase the indentation level.  I previously achieved this with
(c-set-offset 'innamespace 0); Can anyone spell out how to achieve this
under treesitter?

Thanks!

L-G