Export location flags

Also mark assistance_provider_interface as is_exported: true
This allows apps to depend on the flagged APIs

Bug: 401741230
Flag: EXEMPT flag config update
Test: m all_aconfig_declarations
Test: printflags --format='{fully_qualified_name}:{is_exported}' | grep true
Change-Id: Ib8601b69d69d621d30fbcf4a31d6233ceb6f9d18