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>

shared/browser/templates/macros/search.html

@@ -11,18 +11,18 @@
         name="search"
         aria-label="search"
         class="text-base md:text-sm col-span-5 rounded-md px-3 py-2 mb-2 w-full min-w-0 max-w-full border-2 border-stone-200 placeholder-shown:border-stone-200 [&:not(:placeholder-shown)]:border-yellow-200"
-        hx-preserve
+        sx-preserve
         value="{{ search|default('', true) }}"
         placeholder="search"
-        hx-trigger="input changed delay:300ms"
-        hx-target="#main-panel"
+        sx-trigger="input changed delay:300ms"
+        sx-target="#main-panel"
 
-        hx-select="{{hx_select}}, #search-mobile-wrapper, #search-desktop-wrapper"
-        hx-get="{{ (current_local_href ~ {'search': None}|qs)|host }}"
-        hx-swap="outerHTML"
-        hx-push-url="true"
-        hx-headers='{"X-Origin":"search-mobile",  "X-Search":"true"}'
-        hx-sync="this:replace"
+        sx-select="{{hx_select}}, #search-mobile-wrapper, #search-desktop-wrapper"
+        sx-get="{{ (current_local_href ~ {'search': None}|qs)|host }}"
+        sx-swap="outerHTML"
+        sx-push-url="true"
+        sx-headers='{"X-Origin":"search-mobile",  "X-Search":"true"}'
+        sx-sync="this:replace"
         autocomplete="off"
       >
 
@@ -51,18 +51,18 @@
       name="search"
       aria-label="search"
       class="w-full mx-1 my-3 px-3 py-2 text-md rounded-xl border-2 shadow-sm border-white placeholder-shown:border-white [&:not(:placeholder-shown)]:border-yellow-200"
-      hx-preserve
+      sx-preserve
       value="{{ search|default('', true) }}"
       placeholder="search"
-      hx-trigger="input changed delay:300ms"
-      hx-target="#main-panel"
+      sx-trigger="input changed delay:300ms"
+      sx-target="#main-panel"
 
-      hx-select="{{hx_select}}, #search-mobile-wrapper, #search-desktop-wrapper"
-      hx-get="{{ (current_local_href ~ {'search': None}|qs)|host}}"
-      hx-swap="outerHTML"
-      hx-push-url="true"
-      hx-headers='{"X-Origin":"search-desktop", "X-Search":"true"}'
-      hx-sync="this:replace"
+      sx-select="{{hx_select}}, #search-mobile-wrapper, #search-desktop-wrapper"
+      sx-get="{{ (current_local_href ~ {'search': None}|qs)|host}}"
+      sx-swap="outerHTML"
+      sx-push-url="true"
+      sx-headers='{"X-Origin":"search-desktop", "X-Search":"true"}'
+      sx-sync="this:replace"
 
       autocomplete="off"
     >