Make composd API more async

Allow for notification on success/failure and for early cancellation.

Remove the old fully synchronous API.

Migrate the test to use the API (via modifying the composd_cmd tool).

Bug: 204044765
Test: atest ComposTestCase
Test: manual - make timeout very short, observe cancellation
Change-Id: I1d614ed60bc8baa9d4e58c1ca915e2093aec0808
diff --git a/compos/composd/src/composd_main.rs b/compos/composd/src/composd_main.rs
index 60aeb39..671ed16 100644
--- a/compos/composd/src/composd_main.rs
+++ b/compos/composd/src/composd_main.rs
@@ -18,10 +18,12 @@
 //! responsible for managing the lifecycle of the CompOS VM instances, providing key management for
 //! them, and orchestrating trusted compilation.
 
+mod compilation_task;
 mod instance_manager;
 mod instance_starter;
 mod odrefresh;
 mod service;
+mod util;
 
 use crate::instance_manager::InstanceManager;
 use android_system_composd::binder::{register_lazy_service, ProcessState};