Add types for complex access path suggestions

[shati-patel]

Adds a bunch of types that we'll need for showing complex access path suggestions in the model editor. See internal linked issue for more context.

Note: these currently aren't used (and will probably break the deadcode CI check 🙃)

Checklist

N/A

• CHANGELOG.md has been updated to incorporate all user visible changes made by this pull request.
• Issues have been created for any UI or other user-facing changes made by this pull request.
• [Maintainers only] If this pull request makes user-facing changes that require documentation changes, open a corresponding docs pull request in the github/codeql repo and add the ready-for-doc-review label there.

[shati-patel]

Closing this for now. Even when unexporting the types, a bunch of definitions still aren't used, so this PR would become pretty empty. It makes more sense to include the relevant types along with their usage, e.g. in #3292