fix(rock): 兼容 0666.pro 接口 points 字段字符串与数值自适应解析

1. 新增 FlexibleFloat64 类型，解决上游 /api/me 响应中 points 为字符串（如 '8271.2'）导致反序列化失败的问题；
2. 服务层与数据库快照存储统一调用 Float64() 保持类型严谨；
3. 单元测试补充真实上游字符串响应场景并全绿通过。

backend/internal/service/provider_rock_test.go

@@ -285,7 +285,7 @@ func TestRockService_StatsAndPurchase(t *testing.T) {
 					"id":       10028,
 					"username": "王大锤",
 					"role":     "merchant",
-					"points":   8271.2,
+					"points":   "8271.2", // 真实上游 0666.pro 返回字符串格式
 					"status":   "active",
 				},
 			})

backend/internal/service/rock_client.go

@@ -8,10 +8,51 @@ import (
 	"io"
 	"net/http"
 	"net/url"
+	"strconv"
 	"strings"
 	"time"
 )
 
+// FlexibleFloat64 兼容反序列化 JSON 中的数字或字符串（如 "8271.2"）
+type FlexibleFloat64 float64
+
+func (f *FlexibleFloat64) UnmarshalJSON(b []byte) error {
+	if len(b) == 0 || string(b) == "null" {
+		*f = 0
+		return nil
+	}
+	var n float64
+	if err := json.Unmarshal(b, &n); err == nil {
+		*f = FlexibleFloat64(n)
+		return nil
+	}
+	var s string
+	if err := json.Unmarshal(b, &s); err == nil {
+		s = strings.TrimSpace(s)
+		if s == "" {
+			*f = 0
+			return nil
+		}
+		val, err := strconv.ParseFloat(s, 64)
+		if err != nil {
+			*f = 0
+			return nil
+		}
+		*f = FlexibleFloat64(val)
+		return nil
+	}
+	*f = 0
+	return nil
+}
+
+func (f FlexibleFloat64) MarshalJSON() ([]byte, error) {
+	return json.Marshal(float64(f))
+}
+
+func (f FlexibleFloat64) Float64() float64 {
+	return float64(f)
+}
+
 // RockClient 负责与 0666.pro 平台进行 HTTP 通信
 type RockClient struct {
 	baseURL    string
@@ -33,11 +74,11 @@ func NewRockClient(baseURL string) *RockClient {
 
 type RockMeResponse struct {
 	User struct {
-		ID       uint64  `json:"id"`
-		Username string  `json:"username"`
-		Role     string  `json:"role"`
-		Points   float64 `json:"points"`
-		Status   string  `json:"status"`
+		ID       uint64          `json:"id"`
+		Username string          `json:"username"`
+		Role     string          `json:"role"`
+		Points   FlexibleFloat64 `json:"points"`
+		Status   string          `json:"status"`
 	} `json:"user"`
 	Error string `json:"error,omitempty"`
 }

backend/internal/service/rock_service.go

@@ -150,7 +150,7 @@ func (s *RockService) TestConnection(ctx context.Context, bearerToken string) (*
 	now := time.Now()
 	_ = s.db.WithContext(ctx).Model(&model.RockConfig{}).Where("id = 1").Updates(map[string]interface{}{
 		"username":          me.User.Username,
-		"points":            me.User.Points,
+		"points":            me.User.Points.Float64(),
 		"last_heartbeat_at": now,
 	}).Error
 
@@ -271,7 +271,7 @@ func (s *RockService) PurchaseTokens(ctx context.Context, count int, isAuto bool
 		defer cancel()
 		me, meErr := s.client.GetMe(bgCtx, cfg.BearerToken)
 		if meErr == nil && me != nil {
-			_ = s.db.Model(&model.RockConfig{}).Where("id = 1").Update("points", me.User.Points).Error
+			_ = s.db.Model(&model.RockConfig{}).Where("id = 1").Update("points", me.User.Points.Float64()).Error
 		}
 	}()