Add scope-collected/scope-clear-collected!/scope-emitted primitives

Register hashtable-based scope accessors that bypass the CEK special form
dispatch, for use by adapter-html.sx and shell templates.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

hosts/javascript/platform.py

@@ -1141,6 +1141,8 @@ PRIMITIVES_JS_MODULES: dict[str, str] = {
   PRIMITIVES["scope-emit!"] = scopeEmit;
   PRIMITIVES["scope-peek"] = scopePeek;
   PRIMITIVES["scope-emitted"] = sxEmitted;
+  PRIMITIVES["scope-collected"] = sxCollected;
+  PRIMITIVES["scope-clear-collected!"] = sxClearCollected;
 
   // ---- VM stack primitives ----
   // The VM spec (vm.sx) requires these array-like operations.

hosts/ocaml/bin/sx_server.ml

@@ -224,6 +224,23 @@ let () = Sx_primitives.register "scope-emitted" (fun args ->
     (match stack with List items :: _ -> List items | _ -> List [])
   | _ -> List [])
 
+let () = Sx_primitives.register "scope-collected" (fun args ->
+  match args with
+  | [String name] ->
+    let stack = try Hashtbl.find _scope_stacks name with Not_found -> [] in
+    (match stack with List items :: _ -> List items | _ -> List [])
+  | _ -> List [])
+
+let () = Sx_primitives.register "scope-clear-collected!" (fun args ->
+  match args with
+  | [String name] ->
+    let stack = try Hashtbl.find _scope_stacks name with Not_found -> [] in
+    (match stack with
+     | _ :: rest -> Hashtbl.replace _scope_stacks name (List [] :: rest)
+     | [] -> Hashtbl.replace _scope_stacks name [List []]);
+    Nil
+  | _ -> Nil)
+
 let () = Sx_primitives.register "provide-push!" (fun args ->
   match Sx_primitives.get_primitive "scope-push!" with
   | NativeFn (_, fn) -> fn args | _ -> Nil)