HS: on queue first/last modifier (+2 tests)

parse-on-feat now skips 'queue MODE' tokens before parsing the body,
so 'on foo queue first ...' and 'on foo queue last ...' parse correctly.
Compiler ignores queue mode (catch-all drops unknown parts).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

shared/static/wasm/sx/hs-parser.sx

@@ -2882,6 +2882,7 @@
                                     (true nil))))
                               (true nil))))
                         (consume-having!)
+                        (when (and (= (tp-type) "keyword") (= (tp-val) "queue")) (do (adv!) (adv!)))
                         (let
                           ((having (if (or h-margin h-threshold) (dict "margin" h-margin "threshold" h-threshold) nil)))
                           (let