Add public API and stub implementations for app integrity manager (service).

App integrity manager will accept rules from verifier and evaluate these rules
during install (and accept/reject the install accordingly). For more
information, see the linked bug (and the blocked bug).

Design doc: go/integrity-component-android-infra

Bug: 143689885
Change-Id: Ie965c6cc77987e06e9dea4be8fb49785a7bd08c4
Test: moving only