HS: Group 11 misc — toggle-var-cycle, closest-to, tailwind class, toggle timing (+3 tests)

- parser: `toggle $var between v1 and v2 ...` → `(toggle-var-cycle $var (v1 v2 ...))`
- compiler: emit `(hs-toggle-var-cycle! win var-name values)` for new AST node
- runtime: `hs-toggle-var-cycle!` cycles through a list of values on a variable
- parser: `closest .sel to .target` / `closest #id to .target` / `closest sel to .target`
  now consumes the `to` keyword and parses the target expr instead of defaulting to beingTold
- tokenizer: `read-class-name` handles backslash escapes and allows `(`, `)`, `&`
  chars so Tailwind classes like `group-[:nth-of-type(3)_&]:block` tokenize correctly
- platform.py: `domListen` drives async result via `_driveAsync` after `cekCall`
- test: fixed-time toggle asserts `.foo` IS present after click (toggle started, 10ms window open)
- generate-sx-tests.py: aligned MANUAL_TEST_BODIES for timed toggle with corrected assertion

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

hosts/javascript/platform.py

@@ -2042,8 +2042,8 @@ PLATFORM_DOM_JS = """
     // If lambda takes 0 params, call without event arg (convenience for on-click handlers)
     var wrapped = isLambda(handler)
       ? (lambdaParams(handler).length === 0
-        ? function(e) { try { cekCall(handler, NIL); } catch(err) { console.error("[sx-ref] domListen handler error:", name, err); } }
-        : function(e) { try { cekCall(handler, [e]); } catch(err) { console.error("[sx-ref] domListen handler error:", name, err); } })
+        ? function(e) { try { var r = cekCall(handler, NIL); if (globalThis._driveAsync) globalThis._driveAsync(r); } catch(err) { console.error("[sx-ref] domListen handler error:", name, err); } }
+        : function(e) { try { var r = cekCall(handler, [e]); if (globalThis._driveAsync) globalThis._driveAsync(r); } catch(err) { console.error("[sx-ref] domListen handler error:", name, err); } })
       : handler;
     if (name === "click") logInfo("domListen: click on <" + (el.tagName||"?").toLowerCase() + "> text=" + (el.textContent||"").substring(0,20) + " isLambda=" + isLambda(handler));
     var passiveEvents = { touchstart: 1, touchmove: 1, wheel: 1, scroll: 1 };