ENH: standardize mirror RTD implementations

[nrwslac]

Description

• update MR3/4K2 mirror RTD implementations to match TMO.

Motivation and Context

• KBO mirrors using the same pcds device so updating them all at once makes sense.

How Has This Been Tested?

running on PLC, tested by viewing PCDS device typhos screen.

Where Has This Been Documented?

https://jira.slac.stanford.edu/browse/ECS-6705

Screenshots (if appropriate):

Pre-merge checklist

• Code works interactively
• Code contains descriptive comments
• Test suite passes locally
• Libraries are set to fixed versions and not Always Newest
• Code committed with pre-commit (alternatively pre-commit run --all-files)

[nrwslac]

Resolved merge conflict, need review and approval. @ghalym

[KaushikMalapati]

@nrwslac , do you want to tack on the change to SL1K2 from https://jira.slac.stanford.edu/browse/ECS-6745 in this pr? I don't think I can suggest the change since that file wasn't edited in branch, but the change would be in

lcls-plc-rixs-optics/lcls-plc-rixs-optics/rixs_optics/POUs/PRG_SL1K2_EXIT.TcPOU

Line 82 in 5fd4dcb

{attribute 'pytmc' :='pv: SL1K2:EXIT:FWM:1'}

alongside an ioc rebuild.

[nrwslac]

@KaushikMalapati yea, I can add that to this PR.

[nrwslac]

I'll fix the SL1K2 pv name in the next pull request.

[jyotiphy]

looks good to me