feat: 可扩展档案模式框架 + 内置 3C(电子) 模式

- 新增 category.archive_kind 与 kind_field 字段模板表（迁移 0010）
- 种子 electronics 字段模板 + 3C 品类树（手机/笔记本/平板等）
- 后端按档案模式动态计算完整度/合格：食品沿用 food_detail，
  其它模式走 product.attributes + kind_field
- 新增 GET /api/kind-fields?kind= 接口
- 后台编辑页按品类模式动态渲染规格参数表单
- 公开详情页/接口输出带标签的规格表

Co-Authored-By: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>

api/internal/adminstore/kind.go

@@ -0,0 +1,101 @@
+package adminstore
+
+import "context"
+
+// DefaultKind is used for products whose category has no archive kind (or no
+// category at all).
+const DefaultKind = "generic"
+
+// FoodKind keeps the mature, dedicated food_detail path; every other kind is
+// driven generically by kind_field + product.attributes.
+const FoodKind = "food"
+
+// genericBaseFields are the core completeness fields for any non-food kind.
+// Food keeps its own richer CompletenessFields list.
+var genericBaseFields = []string{"name", "gtin", "brand", "category", "image"}
+
+// KindField describes one editable spec field for an archive kind. It drives
+// both the dynamic admin form and the kind-aware completeness computation.
+type KindField struct {
+	Kind        string   `json:"kind"`
+	FieldKey    string   `json:"field_key"`
+	GroupLabel  string   `json:"group_label"`
+	LabelZH     string   `json:"label_zh"`
+	FieldType   string   `json:"field_type"`
+	Unit        *string  `json:"unit"`
+	Options     []string `json:"options"`
+	Placeholder *string  `json:"placeholder"`
+	SortOrder   int      `json:"sort_order"`
+	Qualified   bool     `json:"qualified"`
+}
+
+// ListKindFields returns the ordered field template for one archive kind.
+func (s *Store) ListKindFields(ctx context.Context, kind string) ([]KindField, error) {
+	rows, err := s.pool.Query(ctx, `
+SELECT kind, field_key, group_label, label_zh, field_type, unit, options,
+       placeholder, sort_order, qualified
+FROM kind_field WHERE kind = $1 ORDER BY sort_order, field_key`, kind)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	out := []KindField{}
+	for rows.Next() {
+		var f KindField
+		if err := rows.Scan(&f.Kind, &f.FieldKey, &f.GroupLabel, &f.LabelZH,
+			&f.FieldType, &f.Unit, &f.Options, &f.Placeholder, &f.SortOrder,
+			&f.Qualified); err != nil {
+			return nil, err
+		}
+		out = append(out, f)
+	}
+	return out, rows.Err()
+}
+
+// kindQualifiedKeys returns, per kind, the attribute keys that count toward the
+// completeness/qualified score. Loaded in one query so list views stay cheap.
+func (s *Store) kindQualifiedKeys(ctx context.Context, q queryer) (map[string][]string, error) {
+	rows, err := s.pool.Query(ctx,
+		"SELECT kind, field_key FROM kind_field WHERE qualified ORDER BY sort_order, field_key")
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	m := map[string][]string{}
+	for rows.Next() {
+		var kind, key string
+		if err := rows.Scan(&kind, &key); err != nil {
+			return nil, err
+		}
+		m[kind] = append(m[kind], key)
+	}
+	return m, rows.Err()
+}
+
+// completenessKeys returns the ordered list of field keys that define a full
+// archive for the given kind.
+func completenessKeys(kind string, qualifiedAttrKeys []string) []string {
+	if kind == FoodKind {
+		return CompletenessFields
+	}
+	keys := make([]string, 0, len(genericBaseFields)+len(qualifiedAttrKeys))
+	keys = append(keys, genericBaseFields...)
+	keys = append(keys, qualifiedAttrKeys...)
+	return keys
+}
+
+// attrPresent reports whether an attribute value is meaningfully filled in.
+func attrPresent(attrs map[string]any, key string) bool {
+	v, ok := attrs[key]
+	if !ok || v == nil {
+		return false
+	}
+	switch t := v.(type) {
+	case string:
+		return t != ""
+	case []any:
+		return len(t) > 0
+	default:
+		return true
+	}
+}