feat: SMP stage 1 (4 harts, per-hart guarded stacks, home-core affinity, IPIs, TLB shootdown, one temporary kernel lock), 4-core storm

crates/domain/src/thread/mod.rs

@@ -306,6 +306,14 @@ impl ThreadTable {
         Ok(id)
     }
 
+    /// Every live thread with its id.
+    pub fn iter(&self) -> impl Iterator<Item = (ThreadId, &Thread)> {
+        self.threads
+            .iter()
+            .enumerate()
+            .filter_map(|(i, t)| Some((ThreadId::from_raw(i as u16), t.as_ref()?)))
+    }
+
     pub fn get(&self, id: ThreadId) -> Result<&Thread, KernelError> {
         let idx = id.raw() as usize;
         self.threads