Closes #31330

Second parts of https://github.com/zed-industries/zed/pull/31335

While the initial fix set the inset during drawing, that was after the
window was resized, resulting in needing to manually resize the window
for the change to properly take effect.

I updated the code to not make the Wayland renderer rely on
`client_inset` being updated by the API user to match with the
decoration mode (given it is supposed to only be used when using CSD).

I might later try to generalize that, and eventually make the
client_inset only defined on window creation (instead of inside
`client_side_decorations`, that would need testing on X) (and maybe also
allow configuration for shadow, but it’s not something I need).

Release Notes:

- Fixed switching from client side decoration to server side decoration
on Wayland