fixes: timeAgo utc parse, reload clears unread, sync-event debug

- detail banner timeAgo: SQLite timestamps are UTC without tz marker,
  JS was parsing them as local. Fixed by appending Z when absent —
  same pattern chat uses. "2h ago" for a 30s-old update is gone.
- banner Reload button now re-fires detail.opened so the collab-buckets
  plugin clears the red dot on the board card and calls mark-card-seen.
  Dismiss (×) still leaves the dot — that's the acknowledgement that
  nothing was actually read.
- instrument /api/relay/poll with a sync_debug field so the JS can
  console.debug what happened on the sync-events sub-request (status,
  count, error body). Helps diagnose "no toast" reports.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

public/js/modules/caldav.js

@@ -340,6 +340,9 @@ function showSyncEventToast(ev) {
 }
 
 function drainSyncEvents(relayRes) {
+    if (relayRes?.sync_debug) {
+        console.debug('[sync-events]', relayRes.sync_debug);
+    }
     const events = Array.isArray(relayRes?.sync_events) ? relayRes.sync_events : [];
     for (const ev of events) showSyncEventToast(ev);
 }

public/js/modules/detail.js

@@ -116,6 +116,10 @@ function showStaleBanner(fresh) {
             state.viewingCard = current;
             renderSidebar(current);
             showContent(current);
+            // Treat the reload as an explicit "I've now seen the new version"
+            // — re-fire detail.opened so collab-buckets clears the red dot
+            // on the board card and persists mark-card-seen to the backend.
+            window.hyprcrd?.hooks?.emit?.('detail.opened', { id: current.id });
         }
         dismissStaleBanner();
     });
@@ -123,7 +127,15 @@ function showStaleBanner(fresh) {
 }
 
 function timeAgo(iso) {
-    const t = new Date(iso).getTime();
+    if (!iso) return '';
+    // SQLite stores CURRENT_TIMESTAMP as UTC without a tz marker
+    // ("2026-04-14 12:34:56"). Without an explicit Z, JS parses it as
+    // local time — off by the tz offset (2h on CEST, hence "2h ago"
+    // for a 30-second-old update).
+    const normalized = String(iso).includes('T') || /[Zz]|[+-]\d\d:?\d\d$/.test(iso)
+        ? iso
+        : iso.replace(' ', 'T') + 'Z';
+    const t = new Date(normalized).getTime();
     if (!isFinite(t)) return '';
     const s = Math.max(0, (Date.now() - t) / 1000);
     if (s < 60)  return `${Math.floor(s)}s ago`;