Add a SPEC-like subscriber that saves orientation automatically

[prjemian]

Realizing that the existing methods for saving and restoring the UB matrix (and associated information) are unusual, make it easier for users, especially novice users.

Create a service / subscriber / callback which automatically saves the information to a local file and provides a function to restore that information. This would provide persistence between sessions. Otherwise, without such, it seems that bluesky sessions are like starting SPEC in fresh mode each time.

Make it easier.

Save the same info as is saved when used as a detector. Remember any geometries that have been used but only most recent settings for each.

[prjemian]

Thinking a YAML file indexed by diffractometer name (obj.name, not the dotted name) would be easy to read, review, and revise by both machine and human.

[prjemian]

See related new work:

• 256

• 279

• 280

[prjemian]

Related to:

• 158