Remove old device factory

[DominicOram]

Fixes #1902

I have already discussed the b16 changes with @douglaswinter and the beamline is not using them anyway.

For the changes to i13-1 we will also need to update https://github.com/DiamondLightSource/imaging-bluesky/blame/b72c6a9eed984cfa4e0b233df90685810b140af1/scripts/plans.py#L250

Instructions to reviewer on how to test:

1. Confirm tests still pass and dodal connect ixx for the changed beamlines gives the same output on this branch and main

Checks for reviewer

• Would the PR title make sense to a scientist on a set of release notes
• If a new device has been added does it follow the standards
• If changing the API for a pre-existing device, ensure that any beamlines using this device have updated their Bluesky plans accordingly
• Have the connection tests for the relevant beamline(s) been run via dodal connect ${BEAMLINE}

[codecov]

Codecov Report

❌ Patch coverage is 98.82353% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 99.02%. Comparing base (5951083) to head (ad483b4).
⚠️ Report is 9 commits behind head on main.

Files with missing lines	Patch %	Lines
src/dodal/beamlines/b18.py	88.88%	1 Missing ⚠️
src/dodal/beamlines/k11.py	90.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1905      +/-   ##
==========================================
- Coverage   99.03%   99.02%   -0.02%     
==========================================
  Files         305      304       -1     
  Lines       11519    11569      +50     
==========================================
+ Hits        11408    11456      +48     
- Misses        111      113       +2     

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[DominicOram]

This will break any of these beamlines if they're not using numtracker see https://diamondlightsource.slack.com/archives/C051NDJH6BZ/p1770382254715929

[DominicOram]

Discussed with @tpoliaw, he's going to pick this up given it has wider ramifications than I realised