feat(web): add fan date range modes and delta column

tests/test_web_queries.py

@@ -197,6 +197,52 @@ def test_up_queries():
             db.close()
 
 
+def test_fans_custom_range_modes():
+    with tempfile.TemporaryDirectory() as tmp:
+        db, q = setup(tmp)
+        try:
+            daily = q.fans(start="2026-10-29", end="2026-10-31")
+            assert daily["mode"] == "daily"
+            assert daily["range_start"] == "2026-10-29"
+            assert daily["range_end"] == "2026-10-31"
+            assert daily["dates"] == list(DATES)
+            assert daily["series"] == [1000, 1010, 1020]
+
+            # 超过一年触发按月峰值模式
+            db.write(lambda conn: conn.execute(
+                "INSERT OR REPLACE INTO up_stat"
+                "(stat_date, mid, follower, following, captured_at, ok) "
+                "VALUES ('2025-01-01', 37754047, 500, NULL, 1, 1)"
+            ))
+            monthly = q.fans(start="2025-01-01", end="2026-10-31")
+            assert monthly["mode"] == "monthly"
+            assert monthly["span_days"] == 669
+            assert monthly["dates"][0] == "2025-01-01"
+            assert monthly["series"][0] == 500
+            assert monthly["dates"][-1] == "2026-10-31"
+            assert monthly["series"][-1] == 1020
+
+            # 同月多条时取峰值日期，并优先较晚日期
+            db.write(lambda conn: conn.execute(
+                "INSERT OR REPLACE INTO up_stat"
+                "(stat_date, mid, follower, following, captured_at, ok) "
+                "VALUES ('2026-10-15', 37754047, 5000, NULL, 1, 1), "
+                "('2026-10-16', 37754047, 5000, NULL, 1, 1)"
+            ))
+            monthly = q.fans(start="2025-01-01", end="2026-10-31")
+            assert monthly["dates"][-1] == "2026-10-16"
+            assert monthly["series"][-1] == 5000
+
+            try:
+                q.fans(start="2026-11-01", end="2026-10-01")
+            except ValueError:
+                pass
+            else:
+                raise AssertionError("start 晚于 end 应报错")
+        finally:
+            db.close()
+
+
 def test_fans_candidates_system_and_export():
     with tempfile.TemporaryDirectory() as tmp:
         db, q = setup(tmp)
@@ -223,6 +269,10 @@ def test_fans_candidates_system_and_export():
             recent = q.fans(days=90)
             assert recent["recent_days"] == 14
             assert [point["stat_date"] for point in recent["recent_points"]] == list(DATES)
+            deltas = {point["stat_date"]: point["delta"] for point in recent["recent_points"]}
+            assert deltas["2026-10-29"] == 100  # 对比 2026-10-01 的 900
+            assert deltas["2026-10-30"] == 10
+            assert deltas["2026-10-31"] == 10
             one_day = q.fans(days=90, recent_days=1)
             assert [point["stat_date"] for point in one_day["recent_points"]] == [DATES[-1]]
 
@@ -262,6 +312,7 @@ def main_test():
     test_growth_and_cold_start()
     test_video_detail_and_trend()
     test_up_queries()
+    test_fans_custom_range_modes()
     test_fans_candidates_system_and_export()
     print("OK: Web 查询层总览/榜单/详情/UP/粉丝/候选/系统测试全部通过")