When a redirect is resolved while accessing repo data from a client wiki,

• the usage should be associated with the redirect target
• the usage of the redirect itself should be tracked (using aspect X or a new R aspect)

When a redirect is created or changed, this should be considered an X change, since it affects all types of usage.

This could be solved by doing a reverse redirect lookup when processing changes: When handing a change for Q12, find all redirects to Q12. Do the change processing for Q12 and all the redirects.