feat(init): spawn service over IPC with per-client allowance refunded on child death; up to 4 death watchers; spawntest on test image

crates/libkos/src/lib.rs

@@ -10,6 +10,7 @@ pub mod fs;
 pub mod input;
 pub mod io;
 mod rt;
+pub mod spawn;
 pub mod start;
 pub mod syscall;