Add keep_parent parameter to add_child and add_item #1116

[m-mohr]

Related Issue(s):

• Arbitrary saving location of child catalogs #1116

Description:

Adds a keep_parent parameter to add_child and add_item to allow keeping the current parent if one is set. This makes the add calls more predictable while keeping backward compatibility.

PR Checklist:

• pre-commit hooks pass locally
• Tests pass (run scripts/test)
• Documentation has been updated to reflect changes, if applicable
• This PR maintains or improves overall codebase code coverage.
• Changes are added to the CHANGELOG. See the docs for information about adding to the changelog.