feat(creator): 监控账号画像采集入库——粉丝/关注/获赞/作品数与作者介绍

抖音 profile/other 响应本就携带画像数据但被丢弃，同步链路也无回填。
- migration 1046: creator_competitor 增加 signature、total_favorited 列及非负约束
- douyin 解析层: TargetProfile 增加签名与计数，total_favorited 兼容字符串大数
- store: UpdateCompetitorProfile 改为画像回填（nil 计数保留原值）
- 同步链路: 作品采集成功后拉取 profile 回填，失败仅记日志不阻断

internal/platform/douyin/connector.go

@@ -316,6 +316,7 @@ type identityEnvelope struct {
 		AvatarThumb *struct {
 			URLList []string `json:"url_list"`
 		} `json:"avatar_thumb"`
+		Signature      string       `json:"signature"`
 		FollowerCount  *int64       `json:"follower_count"`
 		FollowingCount *int64       `json:"following_count"`
 		AwemeCount     *int64       `json:"aweme_count"`
@@ -327,6 +328,14 @@ type identityEnvelope struct {
 // flexibleInt 兼容抖音返回的数字与字符串两种计数形态（total_favorited 实测为大数字符串）。
 type flexibleInt int64
 
+func flexibleIntPtr(value *flexibleInt) *int64 {
+	if value == nil {
+		return nil
+	}
+	converted := int64(*value)
+	return &converted
+}
+
 func (value *flexibleInt) UnmarshalJSON(data []byte) error {
 	text := strings.TrimSpace(string(data))
 	if text == "null" {

internal/platform/douyin/creator_collector.go

@@ -27,11 +27,16 @@ type CreatorCollector struct {
 }
 
 type TargetProfile struct {
-	UID       string
-	SecUID    string
-	UniqueID  string
-	Nickname  string
-	AvatarURL string
+	UID            string
+	SecUID         string
+	UniqueID       string
+	Nickname       string
+	AvatarURL      string
+	Signature      string
+	FollowerCount  *int64
+	FollowingCount *int64
+	TotalFavorited *int64
+	AwemeCount     *int64
 }
 
 // WorkStatistics 是作品详情接口返回的指标快照，用于增长曲线时序采集。
@@ -174,7 +179,11 @@ func (c CreatorCollector) ResolveTarget(ctx context.Context, expectedKey string)
 	if identity.User.AvatarThumb != nil && len(identity.User.AvatarThumb.URLList) > 0 {
 		avatarURL = identity.User.AvatarThumb.URLList[0]
 	}
-	return TargetProfile{UID: identity.User.UID, SecUID: identity.User.SecUID, UniqueID: identity.User.UniqueID, Nickname: identity.User.Nickname, AvatarURL: avatarURL}, nil
+	return TargetProfile{
+		UID: identity.User.UID, SecUID: identity.User.SecUID, UniqueID: identity.User.UniqueID, Nickname: identity.User.Nickname, AvatarURL: avatarURL,
+		Signature: identity.User.Signature, FollowerCount: identity.User.FollowerCount, FollowingCount: identity.User.FollowingCount,
+		TotalFavorited: flexibleIntPtr(identity.User.TotalFavorited), AwemeCount: identity.User.AwemeCount,
+	}, nil
 }
 
 func (c CreatorCollector) ResolveWork(ctx context.Context, workKey string) (TargetProfile, error) {

internal/platform/douyin/creator_collector_test.go

@@ -37,6 +37,33 @@ func TestResolveTargetReturnsVerifiedProfileFields(t *testing.T) {
 	}
 }
 
+func TestResolveTargetExtractsPublicProfileMetrics(t *testing.T) {
+	browser := &collectorBrowser{response: Response{Status: 200, Body: []byte(`{"status_code":0,"user":{"uid":"2328120603967913","sec_uid":"MS4wLjABAAAA9f_a7k0bzVizLYXlpC7R61EIaqJ8Ordug7yp7AB8fGKuuF8Fzqk5_DM-eutXnPIK","unique_id":"96332518739","nickname":"目标","signature":"第一行介绍\n第二行介绍","follower_count":123,"following_count":45,"aweme_count":7,"total_favorited":"98765"}}`)}}
+	profile, err := (CreatorCollector{Browser: browser}).ResolveTarget(context.Background(), "MS4wLjABAAAA9f_a7k0bzVizLYXlpC7R61EIaqJ8Ordug7yp7AB8fGKuuF8Fzqk5_DM-eutXnPIK")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if profile.Signature != "第一行介绍\n第二行介绍" {
+		t.Fatalf("signature: %q", profile.Signature)
+	}
+	if profile.FollowerCount == nil || *profile.FollowerCount != 123 || profile.FollowingCount == nil || *profile.FollowingCount != 45 ||
+		profile.AwemeCount == nil || *profile.AwemeCount != 7 {
+		t.Fatalf("counts: %+v", profile)
+	}
+	// total_favorited 实测为大数字符串，必须经 flexibleInt 兼容解析。
+	if profile.TotalFavorited == nil || *profile.TotalFavorited != 98765 {
+		t.Fatalf("total_favorited: %+v", profile.TotalFavorited)
+	}
+}
+
+func TestResolveTargetToleratesMissingPublicMetrics(t *testing.T) {
+	browser := &collectorBrowser{response: Response{Status: 200, Body: []byte(`{"status_code":0,"user":{"uid":"2328120603967913","sec_uid":"MS4wLjABAAAA9f_a7k0bzVizLYXlpC7R61EIaqJ8Ordug7yp7AB8fGKuuF8Fzqk5_DM-eutXnPIK","nickname":"目标"}}`)}}
+	profile, err := (CreatorCollector{Browser: browser}).ResolveTarget(context.Background(), "MS4wLjABAAAA9f_a7k0bzVizLYXlpC7R61EIaqJ8Ordug7yp7AB8fGKuuF8Fzqk5_DM-eutXnPIK")
+	if err != nil || profile.Signature != "" || profile.FollowerCount != nil || profile.TotalFavorited != nil {
+		t.Fatalf("target profile without metrics: %+v err=%v", profile, err)
+	}
+}
+
 func TestCanonicalTargetSecUIDRejectsUniqueIDLookup(t *testing.T) {
 	browser := &collectorBrowser{}
 	_, err := (CreatorCollector{Browser: browser}).CanonicalTargetSecUID(context.Background(), "creator_handle")