test(axum): prove registry dispatch boundary

Exercise registered sync and async handles through public dispatch_async, prove membership semantics, and serialize shared-boundary tests so mutation workers remain deterministic.

req: axum_integration/003

req: public_api/001

hemx-axum/tests/response.rs

@@ -19,6 +19,7 @@ use std::sync::atomic::{AtomicUsize, Ordering};
 use tower::ServiceExt;
 
 static MUTATION_CALLS: AtomicUsize = AtomicUsize::new(0);
+static BOUNDARY_TEST_LOCK: std::sync::Mutex<()> = std::sync::Mutex::new(());
 
 async fn bounded_mutation(_: InteractionRequest) -> StatusCode {
     MUTATION_CALLS.fetch_add(1, Ordering::SeqCst);
@@ -40,6 +41,9 @@ async fn multipart_mutation(request: InteractionRequest) -> StatusCode {
 #[tokio::test]
 async fn interaction_boundary_honors_media_type_and_host_body_limit() {
     // test req: security/003
+    let _guard = BOUNDARY_TEST_LOCK
+        .lock()
+        .unwrap_or_else(|error| error.into_inner());
     MUTATION_CALLS.store(0, Ordering::SeqCst);
     let app = Router::new()
         .route("/mutate", post(bounded_mutation))
@@ -100,6 +104,9 @@ async fn interaction_boundary_honors_media_type_and_host_body_limit() {
 
 #[tokio::test]
 async fn interaction_boundary_extracts_multipart_fields_and_files() {
+    let _guard = BOUNDARY_TEST_LOCK
+        .lock()
+        .unwrap_or_else(|error| error.into_inner());
     let boundary = "hemx-boundary";
     let body = concat!(
         "--hemx-boundary\r\n",
@@ -134,6 +141,9 @@ async fn interaction_boundary_extracts_multipart_fields_and_files() {
 
 #[tokio::test]
 async fn interaction_boundary_skips_unnamed_parts_and_rejects_invalid_multipart() {
+    let _guard = BOUNDARY_TEST_LOCK
+        .lock()
+        .unwrap_or_else(|error| error.into_inner());
     let accepted = concat!(
         "--b\r\n",
         "Content-Disposition: form-data; filename=\"ignored.txt\"\r\n\r\n",
@@ -781,6 +791,32 @@ fn interactions_dispatch_by_checked_handle() {
     assert_eq!(response.batch.ops, vec![title.text("Hello")]);
 }
 
+#[tokio::test]
+async fn registry_contains_registered_sync_and_async_handles_and_async_falls_back_to_sync() {
+    let sync = Handle::<()>::new(21);
+    let asynchronous = Handle::<()>::new(22);
+    let registry = interactions(BuildFingerprint(55))
+        .on(sync, |_| Slot::<String>::new(1).text("sync"))
+        .on_async(asynchronous, |_| async {
+            Slot::<String>::new(1).text("async")
+        });
+
+    assert!(registry.contains(sync.id().id));
+    assert!(registry.contains(asynchronous.id().id));
+    assert!(!registry.contains(99));
+
+    let sync_response = InteractionRequest::from(InteractionForm::for_handle(sync, []))
+        .dispatch_async(registry)
+        .await
+        .unwrap();
+    assert_eq!(sync_response.batch.fingerprint, BuildFingerprint(55));
+    assert_eq!(
+        sync_response.batch.ops,
+        vec![Slot::<String>::new(1).text("sync")]
+    );
+    // test req: axum_integration/003 req: public_api/001
+}
+
 #[test]
 fn interactions_reject_unknown_handle_ids() {
     let request = InteractionRequest::from(InteractionForm::new(9, []));