Add debug logging to page registry pipeline

Server-side: log page count, output size, and first 200 chars in _build_pages_sx.
Client-side: log script tag count, text length, parsed entry count in processPageScripts.
Helps diagnose why pages: 0 routes loaded.

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

shared/sx/ref/boot.sx

@@ -306,19 +306,23 @@
     ;; Process <script type="text/sx-pages"> tags.
     ;; Parses SX page registry and builds route entries with parsed patterns.
     (let ((scripts (query-page-scripts)))
+      (log-info (str "pages: found " (len scripts) " script tags"))
       (for-each
         (fn (s)
           (when (not (is-processed? s "pages"))
             (mark-processed! s "pages")
             (let ((text (dom-text-content s)))
-              (when (and text (not (empty? (trim text))))
+              (log-info (str "pages: script text length=" (if text (len text) 0)))
+              (if (and text (not (empty? (trim text))))
                 (let ((pages (parse text)))
+                  (log-info (str "pages: parsed " (len pages) " entries"))
                   (for-each
                     (fn (page)
                       (append! _page-routes
                         (merge page
                           {"parsed" (parse-route-pattern (get page "path"))})))
-                    pages))))))
+                    pages))
+                (log-warn "pages: script tag is empty")))))
         scripts)
       (log-info (str "pages: " (len _page-routes) " routes loaded")))))