Use eval-expr not aser in handler dispatch

aser in SX doesn't have access to helper/now/state-get. eval-expr
evaluates the body in the current env, returns the AST. The OCaml
handler interception then calls aser server-side with the full env.

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

sx/sx/handlers/dispatch.sx

@@ -41,9 +41,9 @@
     (params body closure)
     (if
       (or (nil? params) (empty? params))
-      (aser body)
+      (eval-expr body)
       (let
         ((bindings (map (fn (p) (let ((name (if (symbol? p) (symbol-name p) (str p)))) (if (= name "&key") nil (if (= name "&rest") nil (let ((val (or (request-arg name) (request-form name)))) (list (make-symbol name) (or val nil))))))) (filter (fn (p) (let ((name (if (symbol? p) (symbol-name p) (str p)))) (and (not (= name "&key")) (not (= name "&rest"))))) params))))
         (let
           ((let-form (list (quote let) (filter (fn (b) (not (nil? b))) bindings) body)))
-          (aser let-form))))))
+          (eval-expr let-form))))))