feat(dashboard): auto-refresh after sync, configurable polling, extra filters

- Detect missed sync completions via last_run.run_id comparison
- Load polling interval from settings (dashboard_poll_seconds, default 5s)
- Add 1min/3min scheduler interval options
- Add 1zi/2zile period filter options
- New Dashboard settings card for polling interval

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

api/app/static/js/settings.js

@@ -69,6 +69,7 @@ async function loadSettings() {
         if (el('settGomagApiShop')) el('settGomagApiShop').value = data.gomag_api_shop || '';
         if (el('settGomagDaysBack')) el('settGomagDaysBack').value = data.gomag_order_days_back || '7';
         if (el('settGomagLimit')) el('settGomagLimit').value = data.gomag_limit || '100';
+        if (el('settDashPollSeconds')) el('settDashPollSeconds').value = data.dashboard_poll_seconds || '5';
     } catch (err) {
         console.error('loadSettings error:', err);
     }
@@ -89,6 +90,7 @@ async function saveSettings() {
         gomag_api_shop: el('settGomagApiShop')?.value?.trim() || '',
         gomag_order_days_back: el('settGomagDaysBack')?.value?.trim() || '7',
         gomag_limit: el('settGomagLimit')?.value?.trim() || '100',
+        dashboard_poll_seconds: el('settDashPollSeconds')?.value?.trim() || '5',
     };
     try {
         const res = await fetch('/api/settings', {