Native bytecode compiler: 8x faster, compile-blob command

Rewrite compile-modules.js to use the native OCaml sx_server binary
instead of the js_of_ocaml kernel in Node.js. Compiles 23 modules in
23s (was 3+ minutes). Uses batch epoch protocol with latin1 encoding
to preserve byte positions for multi-byte UTF-8 content.

- Add compile-blob server command: parse source natively, compile via
  SX compile-module, return bytecode dict
- Fix orchestration.sxbc.json and boot.sxbc.json — never compiled
  successfully with the old JS kernel, now work with native compiler
- Auto-copy compiled bytecode to shared/static/wasm/sx/ for serving

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

hosts/ocaml/bin/sx_server.ml

@@ -829,6 +829,29 @@ let rec dispatch env cmd =
     let src = read_blob () in
     dispatch env (List [Symbol "eval"; String src])
 
+  | List [Symbol "compile-blob"] ->
+    (* Read source as blob, parse natively in OCaml, compile via SX compile-module.
+       Returns the bytecode dict as SX text. Much faster than JS kernel. *)
+    let src = read_blob () in
+    (try
+      let exprs = Sx_parser.parse_all src in
+      let compile_module = env_get env "compile-module" in
+      let result = Sx_ref.cek_call compile_module (List [List exprs]) in
+      let rec raw_serialize = function
+        | Nil -> "nil"
+        | Bool true -> "true" | Bool false -> "false"
+        | Number n -> if Float.is_integer n then string_of_int (int_of_float n) else Printf.sprintf "%g" n
+        | String s -> "\"" ^ escape_sx_string s ^ "\""
+        | Symbol s -> s | Keyword k -> ":" ^ k
+        | List items | ListRef { contents = items } -> "(" ^ String.concat " " (List.map raw_serialize items) ^ ")"
+        | Dict d -> let pairs = Hashtbl.fold (fun k v acc -> (Printf.sprintf ":%s %s" k (raw_serialize v)) :: acc) d [] in "{" ^ String.concat " " pairs ^ "}"
+        | SxExpr s -> s | _ -> "nil"
+      in
+      send_ok_raw (raw_serialize result)
+    with
+    | Eval_error msg -> send_error msg
+    | exn -> send_error (Printexc.to_string exn))
+
   | List [Symbol "eval"; String src] ->
     (try
       let exprs = Sx_parser.parse_all src in