Send all responses as sexp wire format with client-side rendering

- Server sends sexp source text, client (sexp.js) renders everything
- SexpExpr marker class for nested sexp composition in serialize()
- sexp_page() HTML shell with data-mount="body" for full page loads
- sexp_response() returns text/sexp for OOB/partial responses
- ~app-body layout component replaces ~app-layout (no raw!)
- ~rich-text is the only component using raw! (for CMS HTML content)
- Fragment endpoints return text/sexp, auto-wrapped in SexpExpr
- All _*_html() helpers converted to _*_sexp() returning sexp source
- Head auto-hoist: sexp.js moves meta/title/link/script[ld+json]
  from rendered body to document.head automatically
- Unknown components render warning box instead of crashing page
- Component kwargs preserve AST for lazy rendering (fixes <> in kwargs)
- Fix unterminated paren in events/sexp/tickets.sexpr

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

cart/sexp/overview.sexpr

@@ -2,11 +2,11 @@
 
 (defcomp ~cart-badge (&key icon text)
   (span :class "inline-flex items-center gap-1 px-2 py-0.5 rounded-full bg-stone-100"
-    (i :class icon :aria-hidden "true") (raw! text)))
+    (i :class icon :aria-hidden "true") text))
 
-(defcomp ~cart-badges-wrap (&key badges-html)
+(defcomp ~cart-badges-wrap (&key badges)
   (div :class "mt-1 flex flex-wrap gap-2 text-xs text-stone-600"
-    (raw! badges-html)))
+    badges))
 
 (defcomp ~cart-group-card-img (&key src alt)
   (img :src src :alt alt :class "h-16 w-16 rounded-xl object-cover border border-stone-200 flex-shrink-0"))
@@ -16,29 +16,29 @@
     (i :class "fa fa-store text-stone-400 text-xl" :aria-hidden "true")))
 
 (defcomp ~cart-mp-subtitle (&key title)
-  (p :class "text-xs text-stone-500 truncate" (raw! title)))
+  (p :class "text-xs text-stone-500 truncate" title))
 
-(defcomp ~cart-group-card (&key href img-html display-title subtitle-html badges-html total)
+(defcomp ~cart-group-card (&key href img display-title subtitle badges total)
   (a :href href :class "block rounded-2xl border border-stone-200 bg-white shadow-sm hover:shadow-md hover:border-stone-300 transition p-4 sm:p-5"
     (div :class "flex items-start gap-4"
-      (raw! img-html)
+      img
       (div :class "flex-1 min-w-0"
-        (h3 :class "text-base sm:text-lg font-semibold text-stone-900 truncate" (raw! display-title))
-        (raw! subtitle-html) (raw! badges-html))
+        (h3 :class "text-base sm:text-lg font-semibold text-stone-900 truncate" display-title)
+        subtitle badges)
       (div :class "text-right flex-shrink-0"
-        (div :class "text-lg font-bold text-stone-900" (raw! total))
+        (div :class "text-lg font-bold text-stone-900" total)
         (div :class "mt-1 text-xs text-emerald-700 font-medium" "View cart \u2192")))))
 
-(defcomp ~cart-orphan-card (&key badges-html total)
+(defcomp ~cart-orphan-card (&key badges total)
   (div :class "rounded-2xl border border-dashed border-amber-300 bg-amber-50/60 p-4 sm:p-5"
     (div :class "flex items-start gap-4"
       (div :class "h-16 w-16 rounded-xl bg-amber-100 flex items-center justify-center flex-shrink-0"
         (i :class "fa fa-shopping-cart text-amber-500 text-xl" :aria-hidden "true"))
       (div :class "flex-1 min-w-0"
         (h3 :class "text-base sm:text-lg font-semibold text-stone-900" "Other items")
-        (raw! badges-html))
+        badges)
       (div :class "text-right flex-shrink-0"
-        (div :class "text-lg font-bold text-stone-900" (raw! total))))))
+        (div :class "text-lg font-bold text-stone-900" total)))))
 
 (defcomp ~cart-empty ()
   (div :class "max-w-full px-3 py-3 space-y-3"
@@ -47,6 +47,6 @@
         (i :class "fa fa-shopping-cart text-stone-500 text-sm sm:text-base" :aria-hidden "true"))
       (p :class "text-base sm:text-lg font-medium text-stone-800" "Your cart is empty"))))
 
-(defcomp ~cart-overview-panel (&key cards-html)
+(defcomp ~cart-overview-panel (&key cards)
   (div :class "max-w-full px-3 py-3 space-y-3"
-    (div :class "space-y-4" (raw! cards-html))))
+    (div :class "space-y-4" cards)))