Merge orders and positions into one card and hide stale pending when CTP is off.

Stop showing DB pending orders while disconnected, invalidate session cache when CTP is down, and add a local DB clear script without embedded credentials.

Co-authored-by: Cursor <cursoragent@cursor.com>

static/css/trade.css

@@ -2,8 +2,17 @@
 /* 持仓监控页 — 与 split-grid（关键位监控）同宽，全端自适应 */
 .trade-page{width:100%}
 .trade-split{margin-bottom:1.25rem}
-.trade-split .card{min-height:320px}
+.trade-split .card{min-height:360px}
 .trade-split .trade-card#order{margin-bottom:.75rem}
+.trading-live-body{gap:0}
+.trading-live-section{padding-bottom:.5rem}
+.trading-live-section.trading-live-positions{
+    margin-top:.65rem;padding-top:.75rem;border-top:1px solid var(--card-border);
+}
+.trading-live-subtitle{
+    font-size:.82rem;font-weight:600;color:var(--text-muted);
+    margin:0 0 .45rem .15rem;letter-spacing:.02em;
+}
 .sync-badge{font-size:.72rem;font-weight:400;margin-left:.35rem}
 .trade-top-bar{
     display:flex;flex-wrap:wrap;gap:.65rem 1rem;