Improve project documentation concerning API

Uploaded IFC Model can't be set as Standard Model

Git "View Differences" results in 500 error in Repository module.

Impossible to identify errors when bulk moving / updating project

wrong position of "slice edit" - context menu

Incorrect label causes screenreader problems

Member updated mails cannot be surpressed

Try to open OpenProject API: Failed to load API definition.

Remote attachments cache isn't cleared

Form configuration query can not be edited if invalid