[Bug]: Location Group endpoint doesn't allow for updating metadata

[adamkorynta]

Describe the bug

The location group POST endpoint calls cwms_loc.create_loc_group which throws an error if the group already exists. The PATCH endpoint supports rename and updating assigned locations. This means neither endpoint supports editing the shared loc ref, shared loc alias id, description, or attribute metadata fields.

Expected behavior

PATCH should handle the update.

To Reproduce

1. store a loc group with those nullable metadata fields as null
2. try to store the same loc group now with those fields defined

Priority

Medium

Logs/Incident Identifier

No response

CURL Commands

CDA Version

2026.08.14-testa

Additional context

No response

[rma-bryson]

@MikeNeilson - should I create a jira ticket for this issue? Seems like update for location-groups is broken and should get fixed