F permission docs

Summary

For https://gitlab.indiscale.com/caosdb/internal/all/-/issues/598. Adds an example to the code gallery that reproduces the curator role permissions that are in place at ZMT.

Focus

There is a complete new example in src/doc/gallery. Are the explanations understandable?

Test Environment

1. make doc
2. follow the explanations
3. check that a curator user has write permissions to all entities (in particular one that hasn't been inserted by themselves) but the ones defined in the schemata.

Check List for the Author

Please, prepare your MR for a review. Be sure to write a summary and a focus and create gitlab comments for the reviewer. They should guide the reviewer through the changes, explain your changes and also point out open questions. For further good practices have a look at our review guidelines

• All automated tests pass
• Reference related issues
• Up-to-date CHANGELOG.md (or not necessary)
• Annotations in code (Gitlab comments)
  • Intent of new code
  • Problems with old code
  • Why this implementation?

Check List for the Reviewer

• I understand the intent of this MR
• All automated tests pass
• Up-to-date CHANGELOG.md (or not necessary)
• The test environment setup works and the intended behavior is reproducible in the test environment
• In-code documentation and comments are up-to-date.
• Check: Are there specifications? Are they satisfied?

For further good practices have a look at our review guidelines.