morgul mask: should fetch pedestal from JUNGFRAU_CALIBRATION_LOG

At the moment it needs to be passed manually but this is probably unnecessary

Start by locating where the pedestal is currently passed manually and how JUNGFRAU_CALIBRATION_LOG is accessed. Done means the pedestal is fetched from that log without requiring manual input; the issue does not name specific files or tests to run.

索引モデルが issue の本文から書いたものです。