HS: contains/matches ignoring case support — 425→426

- Parser: contains/matches with ignoring case modifier
- Compiler: contains-ignore-case? → hs-contains-ignore-case?
- Compiler: matches-ignore-case? → hs-matches-ignore-case?
- Runtime: downcase-based case-insensitive contains/matches

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

lib/hyperscript/compiler.sx

@@ -688,11 +688,21 @@
                   (quote hs-matches?)
                   (hs-to-sx (nth ast 1))
                   (hs-to-sx (nth ast 2))))
+              ((= head (quote matches-ignore-case?))
+                (list
+                  (quote hs-matches-ignore-case?)
+                  (hs-to-sx (nth ast 1))
+                  (hs-to-sx (nth ast 2))))
               ((= head (quote contains?))
                 (list
                   (quote hs-contains?)
                   (hs-to-sx (nth ast 1))
                   (hs-to-sx (nth ast 2))))
+              ((= head (quote contains-ignore-case?))
+                (list
+                  (quote hs-contains-ignore-case?)
+                  (hs-to-sx (nth ast 1))
+                  (hs-to-sx (nth ast 2))))
               ((= head (quote as))
                 (list (quote hs-coerce) (hs-to-sx (nth ast 1)) (nth ast 2)))
               ((= head (quote in?))