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>

blog/bp/admin/routes.py

@@ -14,6 +14,7 @@ from quart import (
 from shared.browser.app.redis_cacher import clear_all_cache
 from shared.browser.app.authz import require_admin
 from shared.browser.app.utils.htmx import is_htmx_request
+from shared.sexp.helpers import sexp_response
 from shared.config import config
 from datetime import datetime
 
@@ -35,10 +36,10 @@ def register(url_prefix):
       tctx = await get_template_context()
       if not is_htmx_request():
           html = await render_settings_page(tctx)
+          return await make_response(html)
       else:
-          html = await render_settings_oob(tctx)
-
-      return await make_response(html)
+          sexp_src = await render_settings_oob(tctx)
+          return sexp_response(sexp_src)
 
     @bp.get("/cache/")
     @require_admin
@@ -49,9 +50,10 @@ def register(url_prefix):
         tctx = await get_template_context()
         if not is_htmx_request():
             html = await render_cache_page(tctx)
+            return await make_response(html)
         else:
-            html = await render_cache_oob(tctx)
-        return await make_response(html)
+            sexp_src = await render_cache_oob(tctx)
+            return sexp_response(sexp_src)
 
     @bp.post("/cache_clear/")
     @require_admin
@@ -61,7 +63,7 @@ def register(url_prefix):
             now = datetime.now()
             from shared.sexp.jinja_bridge import render as render_comp
             html = render_comp("cache-cleared", time_str=now.strftime("%H:%M:%S"))
-            return html
+            return sexp_response(html)
 
         return redirect(url_for("settings.cache"))
     return bp