Move market composition from Python to .sx defcomps (Phase 3)

Python sxc/pages/ functions no longer build nested sx_call chains or
reference leaf component names. Instead they extract data (URLs, prices,
CSRF, cart state) and call a single top-level composition defcomp with
pure data values. The .sx defcomps handle all component-to-component
wiring, iteration (map), and conditional rendering.

New .sx composition defcomps:
- headers.sx: ~market-header-from-data, ~market-desktop-nav-from-data,
  ~market-product-header-from-data, ~market-product-admin-header-from-data
- prices.sx: ~market-prices-header-from-data, ~market-card-price-from-data
- navigation.sx: ~market-mobile-nav-from-data
- cards.sx: ~market-product-cards-content, ~market-card-from-data,
  ~market-cards-content, ~market-landing-from-data
- detail.sx: ~market-product-detail-from-data, ~market-detail-gallery-from-data,
  ~market-detail-info-from-data
- meta.sx: ~market-product-meta-from-data
- filters.sx: ~market-desktop-filter-from-data, ~market-mobile-chips-from-data,
  ~market-mobile-filter-content-from-data, plus 6 sub-composition defcomps

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

market/sx/detail.sx

@@ -92,3 +92,71 @@
 
 (defcomp ~market-landing-content (&key inner)
   (<> (article :class "relative w-full" inner) (div :class "pb-8")))
+
+
+;; ---------------------------------------------------------------------------
+;; Composition: product detail page from data
+;; ---------------------------------------------------------------------------
+
+;; Gallery section from pre-computed data
+(defcomp ~market-detail-gallery-from-data (&key images labels brand like-data has-nav-buttons thumbs)
+  (let ((like-sx (when like-data
+          (~market-like-button
+            :form-id (get like-data "form-id") :action (get like-data "action")
+            :slug (get like-data "slug") :csrf (get like-data "csrf")
+            :icon-cls (get like-data "icon-cls")))))
+    (if images
+      (<>
+        (~market-detail-gallery
+          :inner (~market-detail-gallery-inner
+            :like like-sx
+            :image (get (first images) "src") :alt (get (first images) "alt")
+            :labels (when labels
+              (<> (map (lambda (src) (~market-label-overlay :src src)) labels)))
+            :brand brand)
+          :nav (when has-nav-buttons (~market-detail-nav-buttons)))
+        (when thumbs
+          (~market-detail-thumbs :thumbs
+            (<> (map (lambda (t)
+              (~market-detail-thumb
+                :title (get t "title") :src (get t "src") :alt (get t "alt")))
+              thumbs)))))
+      (~market-detail-no-image :like like-sx))))
+
+;; Right column details from data
+(defcomp ~market-detail-info-from-data (&key extras desc-short desc-html sections)
+  (~market-detail-right-col :inner
+    (<>
+      (when extras
+        (~market-detail-extras :inner
+          (<> (map (lambda (e)
+            (if (= (get e "type") "unit-price")
+              (~market-detail-unit-price :price (get e "value"))
+              (~market-detail-case-size :size (get e "value"))))
+            extras))))
+      (when (or desc-short desc-html)
+        (~market-detail-desc-wrapper :inner
+          (<> (when desc-short (~market-detail-desc-short :text desc-short))
+              (when desc-html (~market-detail-desc-html :html desc-html)))))
+      (when sections
+        (~market-detail-sections :items
+          (<> (map (lambda (s)
+            (~market-detail-section :title (get s "title") :html (get s "html")))
+            sections)))))))
+
+;; Full product detail layout from data
+(defcomp ~market-product-detail-from-data (&key images labels brand like-data
+                                                has-nav-buttons thumbs sticker-items
+                                                extras desc-short desc-html sections)
+  (~market-detail-layout
+    :gallery (~market-detail-gallery-from-data
+      :images images :labels labels :brand brand :like-data like-data
+      :has-nav-buttons has-nav-buttons :thumbs thumbs)
+    :stickers (when sticker-items
+      (~market-detail-stickers :items
+        (<> (map (lambda (s)
+          (~market-detail-sticker :src (get s "src") :name (get s "name")))
+          sticker-items))))
+    :details (~market-detail-info-from-data
+      :extras extras :desc-short desc-short :desc-html desc-html
+      :sections sections)))