Some segment actions are not properly disabled for non-editable segmentation layers

[philippotto]

Context

Annotation for a dataset with a segmentation layer, but where the segmentation layer is not editable.
https://scm.slack.com/archives/C5AKLAV0B/p1689585308901369?thread_ts=1688991494.182429&cid=C5AKLAV0B

Expected Behavior

• "create new group" should be disabled
• user should not be able to rename segments

Current Behavior

• create new group can be clicked but nothing happens
• segments can be renamed (on reload, this change will be lost)

Steps to Reproduce the bug

• Cannot reproduce the bug anymore / needs deeper investigation.

1. create annotation for a dataset that has a segmentation layer but don't create an editable segmentation layer (e.g., only skeleton annotation layer or create a new/empty segmentation layer)
2. make sure the non-empty segmentation layer is visible
3. click on some segments to fill the segment list
4. use context menu on the root group and try to rename segments

[dieknolle3333]

In this list of single segment actions:

and this list of segment group actions:

I am assuming that the only actions that should be possible for visible but uneditable segmentation layers are Remove segment from list and all the mesh actions.
Do you agree or did I misunderstand something?

Edit: Compute Meshes (ad hoc) is currently not working in this case, an error toast appears and the console logs a 400 status code. In other cases, such as an editable segmentation layer, this is working. I don't know whether this means it shouldn't be possible to compute the meshes (same for all the other mesh actions)

[dieknolle3333]

see more details here: https://scm.slack.com/archives/C5AKLAV0B/p1694797660535889