* _get_f_placeholder_args: set ForceValueArgTag

* Update requirements.txt

* skip scalar arg handling in _args_to_device_buffers

* Revert changes to requirements.txt

* add a simple test

* Fix test

---------

Co-authored-by: Andreas Klöckner <inform@tiker.net>

* Add an implementation of vdot to the PytatoPyOpenCLArrayContext np namespace.

* Remove the tests that are just skipped for scalars.

* Respond to comments.

* Ruff version needed to be updated locally.

* implement TransferTo{Host,Device}Mapper

* do not support transfer to same type

* use {to,from}_numpy

* lint fixes

* add comment

* ruff

* disable spurious pylint warning

* add to docs

* more doc fixes

* datawrapper doc

* more doc fixes

* Improve mapper names

* Bring back numpy actx constructor docs

---------

Co-authored-by: Andreas Kloeckner <inform@tiker.net>

* forbid force_device_scalars=False

* attempt to improve compatibility