fix(HEL-356): restore intraday turnover context

Co-authored-by: multica-agent <github@multica.ai>

backend/data/providers/tushare_dashboard.py

@@ -368,6 +368,11 @@ class DashboardMixin:
             basic = basics[0] if basics else {}
         capital = self._latest_capital(ts_code, reference_date)
         float_share = _number(capital.get("float_share"))
+        if not float_share and previous_close:
+            # The hub's canonical valuation table stores market values but not
+            # share counts. circ_mv (10k CNY) / price (CNY) is float shares in
+            # 10k shares, the same unit used by the turnover formula below.
+            float_share = _number(capital.get("circ_mv")) / previous_close
         # rt_k volume is shares; daily_basic float_share is reported in 10k shares.
         turnover_rate = _number(row.get("vol")) / float_share / 100 if float_share else 0
         market_date = reference_date or datetime.now().astimezone().strftime("%Y%m%d")
@@ -389,6 +394,13 @@ class DashboardMixin:
         for item in market_rows:
             item_capital = capital_map.get(str(item.get("ts_code") or ""), {})
             item_float_share = _number(item_capital.get("float_share"))
+            item_previous = _number(
+                item.get("pre_close")
+                if item.get("pre_close") not in (None, "")
+                else item.get("previous_close")
+            )
+            if not item_float_share and item_previous:
+                item_float_share = _number(item_capital.get("circ_mv")) / item_previous
             if item_float_share:
                 market_turnovers.append(_number(item.get("vol")) / item_float_share / 100)
         market_turnover = (