feat: 配置列表分页与钉钉机器人分钟级排队限流

统一 sources/templates/channels/rules 列表为分页响应，避免配置增多时全量返回；按钉钉 access_token 限制每分钟发送并在超限时等待下一分钟，降低触发官方封禁风险。

Co-authored-by: Cursor <cursoragent@cursor.com>

internal/store/rule.go

@@ -66,13 +66,23 @@ func (s *Store) GetRuleBySourceEvent(ctx context.Context, sourceID int, event st
 	return &r, nil
 }
 
-func (s *Store) ListRules(ctx context.Context) ([]model.Rule, error) {
-	rows, err := s.DB.QueryContext(ctx, `SELECT id, source_id, event, template_id, conditions, enabled, created_at, updated_at FROM notification_rule ORDER BY id`)
+func (s *Store) ListRules(ctx context.Context, page PageFilter) ([]model.Rule, int, error) {
+	var count int
+	if err := s.DB.GetContext(ctx, &count, `SELECT COUNT(*) FROM notification_rule`); err != nil {
+		return nil, 0, fmt.Errorf("count rules: %w", err)
+	}
+
+	page.Normalize()
+	rows, err := s.DB.QueryContext(ctx, `SELECT id, source_id, event, template_id, conditions, enabled, created_at, updated_at FROM notification_rule ORDER BY id LIMIT ? OFFSET ?`, page.PageSize, page.Offset())
 	if err != nil {
-		return nil, fmt.Errorf("list rules: %w", err)
+		return nil, 0, fmt.Errorf("list rules: %w", err)
 	}
 	defer rows.Close()
-	return scanRules(rows)
+	rules, err := scanRules(rows)
+	if err != nil {
+		return nil, 0, err
+	}
+	return rules, count, nil
 }
 
 func (s *Store) UpdateRule(ctx context.Context, id int, r *model.Rule, channelIDs []int) error {