Feature: #102072 - Allow redirect filtering by "protected" state

See forge#102072

Description

The Redirects administration module now allows to filter redirects based on the protected state. Additionally, protected redirects now show a lock icon in the list of redirects, so it is better visualized, that a redirect is protected and excluded from automatic deletion (e.g. with redirects:cleanup).

Impact

The administration of redirects has become more user friendly, because users can now easily filter protected redirects in the Redirects administration module.