Pydantic 2 refuses to deserialise PosixPath as Path object

[DiamondJoseph]

As extra validation of a DetectorParams, it would be ideal if the directory field was of type Path. However, when making it a Path and filling it with the tmp_path fixture from unittest, Pydantic refuses to deserialise the DetectorParams.

At the moment it is (str)

Acceptance Criteria

• DetectorParams.directory is of type Path

[DominicOram]

This will involve changes to the mx-bluesky side too. Currently it assumes that the path is a string with a trailing / we must have the trailing / when we put the path into ispyb