fix(emacs): use assoc instead of assq for UNTIL lookup in org-caldav advice

assq uses eq for key comparison, which can fail if the key symbols aren't
identical objects. assoc uses equal, which is what org-caldav itself uses
for rrule-props lookups (e.g., INTERVAL, FREQ).

This fixes DEADLINEs not being added to recurring events with UNTIL dates.

Also adds debug logging to help diagnose any remaining issues - will be
removed once verified working.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

home/roles/emacs/doom/config.el

@@ -167,7 +167,12 @@
     "Advice to add DEADLINE for UNTIL in recurring events."
     (let ((result (funcall orig-fun eventdata-alist)))
       (let* ((rrule-props (alist-get 'rrule-props eventdata-alist))
-             (until-str (cadr (assq 'UNTIL rrule-props))))
+             (until-str (cadr (assoc 'UNTIL rrule-props)))
+             (summary (alist-get 'summary eventdata-alist)))
+        ;; Debug: log what we're seeing (remove after debugging)
+        (when rrule-props
+          (message "CALDAV-DEBUG: %s | rrule-props: %S | until: %s"
+                   (or summary "?") rrule-props until-str))
         (when until-str
           (save-excursion
             (org-back-to-heading t)