Add hub usage help page with settings nav toggle.

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

manual_trading_hub/static/app.css

@@ -8652,6 +8652,82 @@ body.funds-fullscreen-open {
   }
 }
 
+/* ── 使用说明 ── */
+.help-toolbar {
+  margin-bottom: 12px;
+  min-height: 1.2em;
+}
+.help-layout {
+  display: grid;
+  grid-template-columns: minmax(180px, 220px) minmax(0, 1fr);
+  gap: 16px;
+  align-items: start;
+}
+.help-toc-card {
+  padding: 16px 14px 18px;
+  position: sticky;
+  top: 72px;
+}
+.help-toc-title {
+  margin: 0 0 12px;
+  font-size: 0.82rem;
+  font-weight: 700;
+  letter-spacing: 0.04em;
+  color: var(--text-soft);
+  text-transform: uppercase;
+}
+.help-toc-nav {
+  display: flex;
+  flex-direction: column;
+  gap: 4px;
+}
+.help-toc-item {
+  display: block;
+  width: 100%;
+  text-align: left;
+  padding: 8px 10px;
+  border: none;
+  border-radius: 8px;
+  background: transparent;
+  color: var(--text-soft);
+  font-size: 0.88rem;
+  cursor: pointer;
+  transition: background 0.15s, color 0.15s;
+}
+.help-toc-item:hover {
+  background: var(--surface-2, rgba(255, 255, 255, 0.04));
+  color: var(--text);
+}
+.help-toc-item.is-active {
+  background: var(--accent-soft, rgba(59, 130, 246, 0.12));
+  color: var(--accent, #3b82f6);
+  font-weight: 600;
+}
+.help-doc-card {
+  padding: 18px 20px 20px;
+  min-width: 0;
+}
+
+@media (max-width: 960px) {
+  .help-layout {
+    grid-template-columns: 1fr;
+  }
+  .help-toc-card {
+    position: static;
+  }
+  .help-toc-nav {
+    flex-direction: row;
+    flex-wrap: wrap;
+  }
+  .help-toc-item {
+    width: auto;
+    flex: 1 1 auto;
+  }
+  .help-doc-card .strategy-doc-body {
+    max-height: none;
+  }
+}
+
 /* ── 监控页:永续 / 期权分块 ── */
 .hub-monitor-block {
   margin-bottom: 4px;