feat: add Subject async chat with explicit durable publication

crates/builtin-source/src/lib.rs

@@ -108,6 +108,13 @@ pub const BUILTIN_PROFILE_RESOURCES: &[BuiltinProfileResource] = &[
         description: "Code implementation with optional Git/MR review recipe; no universal Ticket conclusion gate.",
         imports: BASE_IMPORT,
     },
+    BuiltinProfileResource {
+        selector: Some("builtin:async-chat"),
+        path: "profiles/async-chat.dcdl",
+        source: include_str!("../../../resources/profiles/async-chat.dcdl"),
+        description: "Explicitly connected Subject chat with bounded references and asynchronous Worker delegation.",
+        imports: NO_IMPORTS,
+    },
     BuiltinProfileResource {
         selector: Some("builtin:companion"),
         path: "profiles/companion.dcdl",

crates/builtin-source/tests/catalog.rs

@@ -39,3 +39,22 @@ fn catalog_import_metadata_has_no_cycles() {
         visit(resource.path, &mut BTreeSet::new());
     }
 }
+
+#[test]
+fn async_chat_is_public_and_does_not_inherit_broader_profile_defaults() {
+    let catalog = builtin_profile_catalog_snapshot();
+    let path = &catalog.entrypoints["builtin:async-chat"];
+    let resource = BUILTIN_PROFILE_RESOURCES
+        .iter()
+        .find(|resource| resource.path == path)
+        .unwrap();
+    assert_eq!(resource.selector, Some("builtin:async-chat"));
+    assert!(!resource.description.is_empty());
+    assert!(resource.imports.is_empty());
+    assert!(
+        !catalog
+            .imports
+            .keys()
+            .any(|request| request.starts_with(&format!("{path}\0")))
+    );
+}