feat(query-api): add richer stats and retention

internal/store/postgres/query.go

@@ -19,6 +19,7 @@ type EventsFilter struct {
 	EventType string
 	Framework string
 	ClientID  string
+	Since     *time.Time // if nil, defaults to 24h ago
 }
 
 func (d *DB) ListRecentEvents(ctx context.Context, f EventsFilter) ([]EventRow, error) {
@@ -29,10 +30,20 @@ func (d *DB) ListRecentEvents(ctx context.Context, f EventsFilter) ([]EventRow,
 		f.Limit = 1000
 	}
 
+	since := f.Since
+	if since == nil {
+		t := time.Now().Add(-24 * time.Hour)
+		since = &t
+	}
+
 	query := "SELECT event_id, ts, type, payload FROM events WHERE 1=1"
 	args := []any{}
 	argN := 1
 
+	query += fmt.Sprintf(" AND ts >= $%d", argN)
+	args = append(args, *since)
+	argN++
+
 	if f.EventType != "" {
 		query += fmt.Sprintf(" AND type = $%d", argN)
 		args = append(args, f.EventType)