VM aser-slot → sx-page-full: single-call page render, 0.55s warm

Compiler fixes:
- Upvalue re-lookup returns own position (uv-index), not parent slot
- Spec: cek-call uses (make-env) not (dict) — OCaml Dict≠Env
- Bootstrap post-processes transpiler Dict→Env for cek_call

VM runtime fixes:
- compile_adapter evaluates constant defines (SPECIAL_FORM_NAMES etc.)
  via execute_module instead of wrapping as NativeFn closures
- Native primitives: map-indexed, some, every?
- Nil-safe HO forms: map/filter/for-each/some/every? accept nil as empty
- expand-components? set in kernel env (not just VM globals)
- unwrap_env diagnostic: reports actual type received

sx-page-full command:
- Single OCaml call: aser-slot body + render-to-html shell
- Eliminates two pipe round-trips (was: aser-slot→Python→shell render)
- Shell statics (component_defs, CSS, pages_sx) cached in Python,
  injected into kernel once, referenced by symbol in per-request command
- Large blobs use placeholder tokens — Python splices post-render,
  pipe transfers ~51KB instead of 2MB

Performance (warm):
- Server total: 0.55s (was ~2s)
- aser-slot VM: 0.3s, shell render: 0.01s, pipe: 0.06s
- kwargs computation: 0.000s (cached)

SX_STANDALONE mode for sx_docs dev (skips fragment fetches).

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

hosts/ocaml/lib/sx_ref.ml

@@ -422,7 +422,7 @@ and step_sf_deref args env kont =
 
 (* cek-call *)
 and cek_call f args =
-  (let a = (if sx_truthy ((is_nil (args))) then (List []) else args) in (if sx_truthy ((is_nil (f))) then Nil else (if sx_truthy ((let _or = (is_lambda (f)) in if sx_truthy _or then _or else (is_callable (f)))) then (cek_run ((continue_with_call (f) (a) ((Dict (Hashtbl.create 0))) (a) ((List []))))) else Nil)))
+  (let a = (if sx_truthy ((is_nil (args))) then (List []) else args) in (if sx_truthy ((is_nil (f))) then Nil else (if sx_truthy ((let _or = (is_lambda (f)) in if sx_truthy _or then _or else (is_callable (f)))) then (cek_run ((continue_with_call (f) (a) ((make_env ())) (a) ((List []))))) else Nil)))
 
 (* reactive-shift-deref *)
 and reactive_shift_deref sig' env kont =