Tetramm sample rate should be configurable per-Run rather than as initialiser argument

[DiamondJoseph]

~1000 samples in exposure time of detector if possible, losing samples once the exposure time becomes too short to maintain.

This must be exposed on the TetrAMM device in dodal, and then a plan stub must be created for this repository

[callumforrester]

Based on https://github.com/DiamondLightSource/i22-bluesky/issues/35#issuecomment-2165315004