Fix header funds flicker and unify settings page top bar.

Preserve SSR fund values when account_snapshot returns null, retry on failure, and show the same instance header panel on system settings.

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

lib/instance/templates/instance_header_panel.html

@@ -32,6 +32,7 @@
                 <span class="risk-status-badge risk-status-{{ risk_status.status|default('normal') }}" id="account-risk-badge" role="status" title="{{ risk_status.reason|default('', true) }}" data-status-label="{{ risk_status.status_label|default('正常') }}"{% if risk_status.freeze_until_ms %} data-freeze-until-ms="{{ risk_status.freeze_until_ms }}"{% endif %}>{{ risk_status.status_label|default('正常') }}</span>
             </div>
             {% include 'instance_theme_toggle.html' %}
+            <button type="button" class="btn-secondary btn-sm instance-header-refresh-funds" id="settings-refresh-funds" title="从交易所拉取最新资金">刷新资金</button>
         </div>
     </div>
     <div class="instance-header-stats-wrap instance-desktop-only">