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>

account/sexp/auth.sexpr

@@ -3,12 +3,12 @@
 (defcomp ~account-login-error (&key error)
   (when error
     (div :class "bg-red-50 border border-red-200 text-red-700 p-3 rounded mb-4"
-      (raw! error))))
+      error)))
 
-(defcomp ~account-login-form (&key error-html action csrf-token email)
+(defcomp ~account-login-form (&key error action csrf-token email)
   (div :class "py-8 max-w-md mx-auto"
     (h1 :class "text-2xl font-bold mb-6" "Sign in")
-    (raw! error-html)
+    error
     (form :method "post" :action action :class "space-y-4"
       (input :type "hidden" :name "csrf_token" :value csrf-token)
       (div
@@ -22,13 +22,13 @@
 (defcomp ~account-device-error (&key error)
   (when error
     (div :class "bg-red-50 border border-red-200 text-red-700 p-3 rounded mb-4"
-      (raw! error))))
+      error)))
 
-(defcomp ~account-device-form (&key error-html action csrf-token code)
+(defcomp ~account-device-form (&key error action csrf-token code)
   (div :class "py-8 max-w-md mx-auto"
     (h1 :class "text-2xl font-bold mb-6" "Authorize device")
     (p :class "text-stone-600 mb-4" "Enter the code shown in your terminal to sign in.")
-    (raw! error-html)
+    error
     (form :method "post" :action action :class "space-y-4"
       (input :type "hidden" :name "csrf_token" :value csrf-token)
       (div
@@ -48,11 +48,11 @@
 (defcomp ~account-check-email-error (&key error)
   (when error
     (div :class "bg-yellow-50 border border-yellow-200 text-yellow-700 p-3 rounded mt-4"
-      (raw! error))))
+      error)))
 
-(defcomp ~account-check-email (&key email error-html)
+(defcomp ~account-check-email (&key email error)
   (div :class "py-8 max-w-md mx-auto text-center"
     (h1 :class "text-2xl font-bold mb-4" "Check your email")
-    (p :class "text-stone-600 mb-2" "We sent a sign-in link to " (strong (raw! email)) ".")
+    (p :class "text-stone-600 mb-2" "We sent a sign-in link to " (strong email) ".")
     (p :class "text-stone-500 text-sm" "Click the link in the email to sign in. The link expires in 15 minutes.")
-    (raw! error-html)))
+    error))