code review fixes: extract method for handling special expiry logic with documentation and type-hints. extacted special expiry constant for 30 days in seconds. add missing return type-hint and fix return-type hint styles in private API.
code review fixes: extract method for handling special expiry logic with documentation and type-hints. extacted special expiry constant for 30 days in seconds. add missing return type-hint and fix return-type hint styles in private API.

robocoder/cache,doctrine/cache,doktorsitesi/cache,doktorsitesi/cache,robocoder/cache