HS runtime: empty/swap/compound events, host-set! fix — 403→423 (51%)

- Fix host-set → host-set! in emit-inc/emit-dec (increment/decrement properties)
- Implement empty/clear command: parser dispatch, compiler, polymorphic runtime
- Implement swap command: parser dispatch, compiler (let+do temp swap pattern)
- Add parse-compound-event-name: joins dot/colon tokens (example.event, htmx:load)
- Add hs-compile to source parser (was only in WASM deploy copy)
- Add clear/swap to tokenizer keywords and cmd-kw? list
- Generator: fix run() with extra args, String.raw support

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

lib/hyperscript/runtime.sx

@@ -444,10 +444,31 @@
       ((dict? v) (= (len (keys v)) 0))
       (true false))))
 ;; Array slicing (inclusive both ends)
-(define hs-first (fn (lst) (first lst)))
+(define
+  hs-empty-target!
+  (fn
+    (target)
+    (cond
+      ((list? target) (for-each (fn (el) (hs-empty-target! el)) target))
+      ((nil? target) nil)
+      (true
+        (let
+          ((tag (dom-get-prop target "tagName")))
+          (cond
+            ((or (= tag "INPUT") (= tag "TEXTAREA"))
+              (let
+                ((input-type (dom-get-prop target "type")))
+                (if
+                  (or (= input-type "checkbox") (= input-type "radio"))
+                  (dom-set-prop target "checked" false)
+                  (dom-set-prop target "value" ""))))
+            ((= tag "FORM") (dom-set-inner-html target ""))
+            (true (dom-set-inner-html target ""))))))))
 ;; Collection: sorted by
-(define hs-last (fn (lst) (last lst)))
+(define hs-first (fn (lst) (first lst)))
 ;; Collection: sorted by descending
+(define hs-last (fn (lst) (last lst)))
+;; Collection: split by
 (define
   hs-template
   (fn
@@ -533,7 +554,7 @@
                   (set! i (+ i 1))
                   (tpl-loop)))))))
       (do (tpl-loop) result))))
-;; Collection: split by
+;; Collection: joined by
 (define
   hs-make-object
   (fn
@@ -545,7 +566,7 @@
           (fn (pair) (dict-set! d (first pair) (nth pair 1)))
           pairs)
         d))))
-;; Collection: joined by
+
 (define
   hs-method-call
   (fn