ART: TI Agent test library refactor

More refactoring, lowering the reliance on ART-provided functionality
and adding a library that includes all the code that can run without
ART.

Bug: 32072923
Test: m test-art-host
Change-Id: I67d84056a6fd7722c58855fccbdea3f6869b2efb
(cherry picked from commit 027444b6)