Fix admin forms

[rgalanakis]

• Product and vendor service create pages weren't working right due to changes around categories (and some other stuff)
• Vendor service create couldn't work right because the mobility adapter options were coming back on the entity, not as a meta endpoint. Add a meta endpoint instead.
• Categories related list can use an admin link for the row id.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 99.81%. Comparing base (2064fdd) to head (641b5d0).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #902   +/-   ##
=======================================
  Coverage   99.81%   99.81%           
=======================================
  Files         703      703           
  Lines       34369    34377    +8     
=======================================
+ Hits        34306    34314    +8     
  Misses         63       63           

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