fix(web): fix UP card layout and fan delta semantics

tests/test_web_queries.py

@@ -171,6 +171,7 @@ def test_up_queries():
         db, q = setup(tmp)
         try:
             ups = q.list_ups()
+            assert ups["sort"] == "avg_views"
             assert ups["total"] == 2
             assert ups["items"][0]["up_mid"] == 1
             assert ups["items"][0]["video_count"] == 2
@@ -212,6 +213,15 @@ def test_fans_candidates_system_and_export():
             wide = q.fans(days=30)
             assert wide["dates"] == list(DATES)
 
+            # 缺失前一天时不能把跨多天的变化标成“日增”
+            db.write(lambda conn: conn.execute(
+                "DELETE FROM up_stat WHERE mid=37754047 AND stat_date=?",
+                ("2026-10-30",),
+            ))
+            gapped = q.fans(days=3)
+            assert gapped["delta_1d"] is None
+            assert gapped["delta_7d"] is None
+
             candidates = q.candidates()
             assert candidates["total"] == 2
             assert candidates["pending"] == 1