`osc` branching from SCM-only projects

[mcepl]

Describe the bug
editors:tree-sitter is a devel project for all tree-sitter-related packages (used by Neovim, Emacs, and Helix text editors, at least). https://build.opensuse.org/project/show/editors:tree-sitter has been converted to Git, so it is now fully under SCM control (Gitea organization is https://src.opensuse.org/tree-sitter/_ObsPrj).

However, osc doesn’t seem to care:

mitmanek~/b/home:mcepl:branches:editors:tree-sitter$ osc branch openSUSE:Factory tree-sitter-rst .
A working copy of the branched package can be checked out with:

osc co home:mcepl:branches:editors:tree-sitter/tree-sitter-rst
mitmanek~/b/home:mcepl:branches:editors:tree-sitter$ osc up
Updating neovim
At revision e5c6bc8d3a7ace18094ade76082ef36c.
Skipping git managed package  tree-sitter
Skipping git managed package  tree-sitter-lua
checking out new package tree-sitter-rst
A    tree-sitter-rst
/home/matej/build/home:mcepl:branches:editors:tree-sitter/tree-sitter-rst/.osc/sources/tree-sitter-rst-0.2.0.tar.gz
A    tree-sitter-rst/tree-sitter-rst-0.2.0.tar.gz
/home/matej/build/home:mcepl:branches:editors:tree-sitter/tree-sitter-rst/.osc/sources/tree-sitter-rst.changes
A    tree-sitter-rst/tree-sitter-rst.changes
/home/matej/build/home:mcepl:branches:editors:tree-sitter/tree-sitter-rst/.osc/sources/tree-sitter-rst.spec
A    tree-sitter-rst/tree-sitter-rst.spec
At revision ad4fcd6c29d83e9745bd359669b35675.
mitmanek~/b/home:mcepl:branches:editors:tree-sitter$ 

Versions

• Operating system: openSUSE/Tumbleweed packages on MicroOS
• Packages: from Git, commit d6aac5c

To Reproduce
Steps to reproduce the behavior:

1. Run command osc branch openSUSE:Factory tree-sitter-rst .
2. There is no error and osc created https://build.opensuse.org/package/show/home:mcepl:branches:editors:tree-sitter/tree-sitter-rst which is derived directly from openSUSE:Factory ignoring the existence of the devel project completely.

Expected behavior
Either error (something in the style “The project editors:tree-sitter is managed by SCM, go away!”) or (even better) the equivalent of osc rmkpac --scmsync 'https://src.opensuse.org/tree-sitter/tree-sitter.git' . tree-sitter-rst

By the way, this is still related to my evergreen openSUSE/openSUSE-git#124 (and the second expected behaviour would be a neat UI improvement over the current need to use osc rmkpac).