All the CDRs are in the table v_xml_cdr on the PostgreSQL database, and the recordings themselves mapped to filenames under /var/lib/freeswitch/recordings/
You can either export this table and the recordings to the necessary location for you to program a frontend. Alternatively, you'll have to allow remote access from a trusted server on both the postgresql database and the /var/lib/freeswitch/recordings directory, probably via HTTP I would guess.
This is all beyond the scope of this forum though and is more of a programming project and not a FusionPBX question.