Prepare for switch to idmap2

Prepare the idmap and asset managers for interfacing with idmap2 instead
of today's installd + idmap pipeline, but don't make the switch just
yet.

Instead, idmap2 runs as its own native daemon with an AIDL interface.
This removes the need for installd to fork and exec on each idmap call,
saving about 50 ms per call.

Bug: 78815803
Test: atest OverlayDeviceTests OverlayHostTests
Change-Id: I60852e15d99329896ff9de6559d1e7cd1c67e33d
diff --git a/services/core/Android.bp b/services/core/Android.bp
index 888ad1d..6174300 100644
--- a/services/core/Android.bp
+++ b/services/core/Android.bp
@@ -3,6 +3,7 @@
 
     aidl: {
         include_dirs: [
+            "frameworks/base/cmds/idmap2/idmap2d/aidl",
             "frameworks/native/aidl/binder",
             "frameworks/native/cmds/dumpstate/binder",
             "system/core/storaged/binder",
@@ -13,6 +14,7 @@
     srcs: [
         "java/**/*.java",
         ":dumpstate_aidl",
+        ":idmap2_aidl",
         ":netd_aidl",
         ":netd_metrics_aidl",
         ":installd_aidl",