feat(table): 表格排序与搜索改为后端处理

backend/internal/pkg/pagination/pagination.go

@@ -1,10 +1,19 @@
 // Package pagination provides types and helpers for paginated responses.
 package pagination
 
+import "strings"
+
+const (
+	SortOrderAsc  = "asc"
+	SortOrderDesc = "desc"
+)
+
 // PaginationParams 分页参数
 type PaginationParams struct {
-	Page     int
-	PageSize int
+	Page      int
+	PageSize  int
+	SortBy    string
+	SortOrder string
 }
 
 // PaginationResult 分页结果
@@ -18,8 +27,9 @@ type PaginationResult struct {
 // DefaultPagination 默认分页参数
 func DefaultPagination() PaginationParams {
 	return PaginationParams{
-		Page:     1,
-		PageSize: 20,
+		Page:      1,
+		PageSize:  20,
+		SortOrder: SortOrderDesc,
 	}
 }
 
@@ -36,8 +46,32 @@ func (p PaginationParams) Limit() int {
 	if p.PageSize < 1 {
 		return 20
 	}
-	if p.PageSize > 100 {
-		return 100
+	if p.PageSize > 1000 {
+		return 1000
 	}
 	return p.PageSize
 }
+
+// NormalizeSortOrder normalizes sort order to asc/desc and falls back to defaultOrder.
+func NormalizeSortOrder(order string, defaultOrder string) string {
+	switch strings.ToLower(strings.TrimSpace(defaultOrder)) {
+	case SortOrderAsc:
+		defaultOrder = SortOrderAsc
+	default:
+		defaultOrder = SortOrderDesc
+	}
+
+	switch strings.ToLower(strings.TrimSpace(order)) {
+	case SortOrderAsc:
+		return SortOrderAsc
+	case SortOrderDesc:
+		return SortOrderDesc
+	default:
+		return defaultOrder
+	}
+}
+
+// NormalizedSortOrder returns the normalized sort order using defaultOrder as fallback.
+func (p PaginationParams) NormalizedSortOrder(defaultOrder string) string {
+	return NormalizeSortOrder(p.SortOrder, defaultOrder)
+}