Restore coupler protocols

[andrea-pasquale]

In #1036 I have temporarily dropped protocols involving couplers. Given that currently we don't have access to a chip with control electronics compatible with qibolab 0.2. I plan to re-add them as soon as possible.

[andrea-pasquale]

This is related to https://www.notion.so/qcomp/List-of-experiments-and-proposals-2412a62db88b80bbb83ad68afcd5a88a?p=2412a62db88b80a6b152c76f6dcbedb4&pm=s
and https://www.notion.so/qcomp/List-of-experiments-and-proposals-2412a62db88b80bbb83ad68afcd5a88a?p=23a2a62db88b80fb9c82f983269772d8&pm=s