Zephyr: Update to Zephyr 4.4

[zingo]

We should update to Zephyr 4.4 in our docs/samples/testing.

cc @digantdesai @freddan80 @per @oscarandersson8218 @mansnils @Sebastian-Larsson @robell

[zingo]

Started and have some work in progress ready for this after a small cleanup/improvment PR train in merged :)