Previously, all errors, warnings and info messages were propagated from the node
that generates it to the top level node group. This is a good default, but may
not always be desirable. For example, someone may build a node group asset that
generates some warning that is irrelevant to the user to the asset. Now, the
asset author can selectively disable propagating warnings from that node.
Each node has a new `Warning Propagation` setting. It controls if warnings from
this node should be propagated to the parent group node. By default, everything
is propagated. One can also choose to propagate nothing, only errors or only
errors and warnings.
Note, this does not affect whether the warning is shown in the node itself, only
if the warning is propagated one level up!
Pull Request: https://projects.blender.org/blender/blender/pulls/126786