Add macros, declarative handlers (defhandler), and convert all fragment routes to sx

Phase 1 — Macros: defmacro + quasiquote syntax (`, ,, ,@) in parser,
evaluator, HTML renderer, and JS mirror. Macro type, expansion, and
round-trip serialization.

Phase 2 — Expanded primitives: app-url, url-for, asset-url, config,
format-date, parse-int (pure); service, request-arg, request-path,
nav-tree, get-children (I/O); jinja-global, relations-from (pure).
Updated _io_service to accept (service "registry-name" "method" :kwargs)
with auto kebab→snake conversion. DTO-to-dict now expands datetime fields
into year/month/day convenience keys. Tuple returns converted to lists.

Phase 3 — Declarative handlers: HandlerDef type, defhandler special form,
handler registry (service → name → HandlerDef), async evaluator+renderer
(async_eval.py) that awaits I/O primitives inline within control flow.
Handler loading from .sx files, execute_handler, blueprint factory.

Phase 4 — Convert all fragment routes: 13 Python fragment handlers across
8 services replaced with declarative .sx handler files. All routes.py
simplified to uniform sx dispatch pattern. Two Jinja HTML handlers
(events/container-cards, events/account-page) kept as Python.

New files: shared/sx/async_eval.py, shared/sx/handlers.py,
shared/sx/tests/test_handlers.py, plus 13 handler .sx files under
{service}/sx/handlers/. MarketService.product_by_slug() added.

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

events/sx/handlers/account-nav-item.sx

@@ -0,0 +1,19 @@
+;; Events account-nav-item fragment handler
+;;
+;; Renders tickets + bookings links for the account dashboard nav.
+
+(defhandler account-nav-item (&key)
+  (let ((styles      (or (jinja-global "styles") (dict)))
+        (nav-class   (or (get styles "nav_button") ""))
+        (hx-select   "#main-panel, #search-mobile, #search-count-mobile, #search-desktop, #search-count-desktop, #menu-items-nav-wrapper"))
+    (<>
+      (~nav-group-link
+        :href (app-url "account" "/tickets/")
+        :hx-select hx-select
+        :nav-class nav-class
+        :label "tickets")
+      (~nav-group-link
+        :href (app-url "account" "/bookings/")
+        :hx-select hx-select
+        :nav-class nav-class
+        :label "bookings"))))

events/sx/handlers/container-nav.sx

@@ -0,0 +1,81 @@
+;; Events container-nav fragment handler
+;;
+;; Renders calendar entry nav items + calendar link nav items
+;; for the scrollable navigation panel on blog post pages.
+;;
+;; Params (from request.args):
+;;   container_type  — "page" (default)
+;;   container_id    — int
+;;   post_slug       — string
+;;   paginate_url    — base URL for infinite scroll
+;;   page            — current page (default 1)
+;;   exclude         — comma-separated exclusion prefixes
+;;   current_calendar — currently selected calendar slug
+
+(defhandler container-nav
+  (&key container_type container_id post_slug paginate_url page exclude current_calendar)
+
+  (let ((ct          (or container_type "page"))
+        (cid         (parse-int (or container_id "0")))
+        (slug        (or post_slug ""))
+        (purl        (or paginate_url ""))
+        (pg          (parse-int (or page "1")))
+        (excl-raw    (or exclude ""))
+        (cur-cal     (or current_calendar ""))
+        (excludes    (filter (fn (e) (not (empty? e)))
+                       (map trim (split excl-raw ","))))
+        (has-cal-excl (not (empty? (filter (fn (e) (starts-with? e "calendar"))
+                                     excludes))))
+        (styles      (or (jinja-global "styles") (dict)))
+        (nav-class   (or (get styles "nav_button") ""))
+        (sel-colours (or (jinja-global "select_colours") "")))
+
+    ;; Only render if no calendar-* exclusion
+    (when (not has-cal-excl)
+      (let ((result   (service "calendar" "associated-entries"
+                        :content-type ct :content-id cid :page pg))
+            (entries  (first result))
+            (has-more (nth result 1))
+            (calendars (service "calendar" "calendars-for-container"
+                         :container-type ct :container-id cid)))
+
+        (<>
+          ;; Calendar entry nav items
+          (map (fn (entry)
+            (let ((entry-path (str "/" slug "/"
+                                   (get entry "calendar_slug") "/"
+                                   (get entry "start_at_year") "/"
+                                   (get entry "start_at_month") "/"
+                                   (get entry "start_at_day")
+                                   "/entries/" (get entry "id") "/"))
+                  (date-str (str (format-date (get entry "start_at") "%b %d, %Y at %H:%M")
+                                 (if (get entry "end_at")
+                                   (str " – " (format-date (get entry "end_at") "%H:%M"))
+                                   ""))))
+              (~calendar-entry-nav
+                :href (app-url "events" entry-path)
+                :name (get entry "name")
+                :date-str date-str
+                :nav-class nav-class))) entries)
+
+          ;; Infinite scroll sentinel
+          (when (and has-more (not (empty? purl)))
+            (~htmx-sentinel
+              :id (str "entries-load-sentinel-" pg)
+              :hx-get (str purl "?page=" (+ pg 1))
+              :hx-trigger "intersect once"
+              :hx-swap "beforebegin"
+              :class "flex-shrink-0 w-1"))
+
+          ;; Calendar link nav items
+          (map (fn (cal)
+            (let ((href (app-url "events" (str "/" slug "/" (get cal "slug") "/")))
+                  (is-selected (if (not (empty? cur-cal))
+                                 (= (get cal "slug") cur-cal)
+                                 false)))
+              (~calendar-link-nav
+                :href href
+                :name (get cal "name")
+                :nav-class nav-class
+                :is-selected is-selected
+                :select-colours sel-colours))) calendars))))))

events/sx/handlers/link-card.sx

@@ -0,0 +1,34 @@
+;; Events link-card fragment handler
+;;
+;; Renders event page preview card(s) by slug.
+;; Supports single mode (?slug=x) and batch mode (?keys=x,y,z).
+
+(defhandler link-card (&key slug keys)
+  (if keys
+    (let ((slugs (filter (fn (s) (not (empty? s)))
+                   (map trim (split keys ",")))))
+      (<> (map (fn (s)
+        (let ((post (query "blog" "post-by-slug" :slug s)))
+          (<> (str "<!-- fragment:" s " -->")
+              (when post
+                (let ((calendars (service "calendar" "calendars-for-container"
+                                   :container-type "page"
+                                   :container-id (get post "id")))
+                      (cal-names (join ", " (map (fn (c) (get c "name")) calendars))))
+                  (~link-card
+                    :title (get post "title")
+                    :image (get post "feature_image")
+                    :subtitle cal-names
+                    :link (app-url "events" (str "/" (get post "slug"))))))))) slugs)))
+    (when slug
+      (let ((post (query "blog" "post-by-slug" :slug slug)))
+        (when post
+          (let ((calendars (service "calendar" "calendars-for-container"
+                             :container-type "page"
+                             :container-id (get post "id")))
+                (cal-names (join ", " (map (fn (c) (get c "name")) calendars))))
+            (~link-card
+              :title (get post "title")
+              :image (get post "feature_image")
+              :subtitle cal-names
+              :link (app-url "events" (str "/" (get post "slug"))))))))))

events/sx/sx_components.py

@@ -21,8 +21,9 @@ from shared.sx.helpers import (
 )
 from shared.sx.parser import SxExpr
 
-# Load events-specific .sx components at import time
-load_service_components(os.path.dirname(os.path.dirname(__file__)))
+# Load events-specific .sx components + handlers at import time
+load_service_components(os.path.dirname(os.path.dirname(__file__)),
+                        service_name="events")
 
 
 # ---------------------------------------------------------------------------