fix: disable test harness for no_std binaries, fix shutdown to best-effort notify-and-halt, use CapSlot newtypes

crates/adapter-riscv/Cargo.toml

@@ -3,6 +3,11 @@ name = "adapter-riscv"
 version = "0.1.0"
 edition = "2024"
 
+[[bin]]
+name = "adapter-riscv"
+test = false
+bench = false
+
 [dependencies]
 types = { workspace = true }
 domain = { workspace = true }

crates/apps/hello/Cargo.toml

@@ -3,6 +3,11 @@ name = "hello"
 version = "0.1.0"
 edition = "2024"
 
+[[bin]]
+name = "hello"
+test = false
+bench = false
+
 [dependencies]
 userspace = { workspace = true }
 

crates/apps/snake/Cargo.toml

@@ -3,6 +3,11 @@ name = "snake"
 version = "0.1.0"
 edition = "2024"
 
+[[bin]]
+name = "snake"
+test = false
+bench = false
+
 [dependencies]
 types = { workspace = true }
 userspace = { workspace = true }

crates/init/src/shutdown.rs

@@ -1,23 +1,23 @@
-const SHUTDOWN_TIMEOUT_TICKS: usize = 50_000_000;
+use types::bounded::CapSlot;
 
-pub fn shutdown(server_endpoints: &[usize], endpoint_count: usize) -> ! {
+const SHUTDOWN_TIMEOUT_TICKS: usize = 50_000_000;
+const SHUTDOWN_SIGNAL: usize = 0xFFFF_FFFF;
+
+/// Best-effort shutdown: notify all servers, wait briefly for them to flush, then halt.
+///
+/// Servers that receive the shutdown signal should flush state to storage and exit.
+/// We can't block on individual acks because a crashed server would deadlock us.
+/// Instead, we yield repeatedly until the timeout expires, giving servers time to finish.
+pub fn shutdown(server_endpoints: &[CapSlot], endpoint_count: usize) -> ! {
     for i in 0..endpoint_count {
-        let ep = server_endpoints[i];
-        if ep != 0 {
-            userspace::syscall::send(ep, 0xFFFF_FFFF, 0, 0, 0);
-        }
+        let ep = server_endpoints[i].value() as usize;
+        userspace::syscall::send(ep, SHUTDOWN_SIGNAL, 0, 0, 0);
     }
 
     let start = userspace::syscall::get_time();
     let deadline = start + SHUTDOWN_TIMEOUT_TICKS;
 
-    let mut acks = 0usize;
-    while acks < endpoint_count {
-        let now = userspace::syscall::get_time();
-        if now >= deadline {
-            break;
-        }
-        acks += 1;
+    while userspace::syscall::get_time() < deadline {
         userspace::syscall::yield_now();
     }