fix: 来源冲突比较升级为广告家族归一（meta/google/bing/yandex 家族）

Co-Authored-By: Claude Code <noreply@anthropic.com>

server/tracker/tests/test_attribution.py

@@ -145,6 +145,33 @@ def test_utm_chinese_alias_baidu_matches():
     assert r["detail"].get("utm_source") == "百度"
 
 
+# ------------------------------------------- 广告家族归一（付费点击参数 ↔ UTM 同家族）
+def test_fbclid_with_utm_fb_same_meta_family_combined():
+    r = classify(landing_path="/?fbclid=IwAR0", utm={"utm_source": "fb"})
+    assert r["channel"] == "paid_search" and r["platform"] == "Meta Ads"
+    assert r["resolution"] == "resolved" and r["evidence_kind"] == "combined"
+    assert r["detail"].get("utm_source") == "fb"       # fb ↔ Meta Ads 同 meta 家族
+
+
+def test_fbclid_with_utm_ig_combined():
+    r = classify(landing_path="/?fbclid=IwAR0", utm={"utm_source": "ig"})
+    assert r["platform"] == "Meta Ads"                 # ig 也在 meta 家族
+    assert r["resolution"] != "conflict" and r["evidence_kind"] == "combined"
+
+
+def test_gclid_with_utm_google_combined():
+    r = classify(landing_path="/offer?gclid=EAIaIQ", utm={"utm_source": "google"})
+    assert r["channel"] == "paid_search" and r["platform"] == "Google Ads"
+    assert r["resolution"] != "conflict" and r["evidence_kind"] == "combined"
+
+
+def test_fbclid_with_utm_tiktok_still_conflict():
+    r = classify(landing_path="/?fbclid=IwAR0", utm={"utm_source": "tiktok"})
+    assert r["resolution"] == "conflict"               # 跨家族（meta vs tiktok）= 真矛盾
+    assert r["detail"]["referrer_evidence"]["platform"] == "Meta Ads"
+    assert r["detail"]["utm_evidence"]["platform"] == "tiktok"
+
+
 def test_utm_only_is_label_only():
     r = classify(utm={"utm_source": "newsletter"})
     assert r["channel"] == "referral"               # 未知标签 → 有名 referral，但状态诚实标注