Merge loops/host-persist into architecture: host durable-storage adapter (persist/* + blob/* on disk, restart-safe)

hosts/ocaml/bin/sx_server.ml

@@ -571,9 +571,12 @@ and cek_run_with_io state =
           Hashtbl.replace d "descent" (Number desc);
           Dict d
         | _ ->
-          let args = let a = Sx_runtime.get_val request (String "args") in
-            (match a with List l -> l | _ -> [a]) in
-          io_request op args
+          let argsv = Sx_runtime.get_val request (String "args") in
+          (match Sx_persist_store.handle_op op argsv with
+           | Some resp -> resp
+           | None ->
+             let args = (match argsv with List l -> l | _ -> [argsv]) in
+             io_request op args)
       in
       s := Sx_ref.cek_resume !s response;
       loop ()
@@ -1698,7 +1701,12 @@ let rec dispatch env cmd =
                | Some path -> load_library_file path | None -> ());
               Nil
             end
-          end else Nil (* non-import IO: resume with nil *) in
+          end else
+            (* durable-storage ops: service against on-disk store *)
+            let args = Sx_runtime.get_val request (String "args") in
+            (match Sx_persist_store.handle_op op args with
+             | Some resp -> resp
+             | None -> Nil (* non-import IO: resume with nil *)) in
           s := Sx_ref.cek_resume !s response
         done;
         Sx_ref.cek_value !s
@@ -4051,7 +4059,10 @@ let http_mode port =
       Dict d
     | "io-sleep" | "sleep" -> Nil
     | "import" -> Nil
-    | _ -> Nil);
+    | _ ->
+      (match Sx_persist_store.handle_op op args with
+       | Some resp -> resp
+       | None -> Nil));
   (* Response cache — path → full HTTP response string.
      Populated during pre-warm, serves cached responses in <0.1ms.
      Thread-safe: reads are lock-free (Hashtbl.find_opt is atomic for