Merge idmap verify/create calls during boot

StartOverlayManagerService currently makes many binder round trips (at
least 1 per package) when verifying resource idmaps and creating them if
necessary. This change adds an idmap AIDL API for verifying+creating
idmaps for mulitple packages so that this work can be done in a single
binder transaction.

In general, the information needed to verify/create an idmap is
accumulated in lists (in the same order as before) before being sent
over in one batch. This saves ~25ms in StartOverlayManagerService.
(173.8ms -> 146ms, avg. over 5 runs).

Test: - atest OverlayManagerImplTest
      - atest OverlayManagerTest
      - atest OverlayManagerServiceImplTests
Bug: 422474410
Flag: android.content.res.merge_idmap_binder_transactions
Change-Id: Ifb0ee1615af1f16c3f75e14d2a650c6e98e01e66