settings: add Exchange API tab for instance system settings.

Allow configuring perpetual API keys and live trading from Settings, reusing the existing env save API.

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

lib/instance/instance_display_prefs_lib.py

@@ -21,6 +21,7 @@ DEFAULT_INSTANCE_DISPLAY: dict[str, bool] = {
     "show_settings_transfer": True,
     "show_settings_export": True,
     "show_settings_password": True,
+    "show_settings_exchange_api": True,
     "show_settings_options_swap": True,
     "show_settings_options_transfer": True,
 }
@@ -39,6 +40,7 @@ DISPLAY_LABELS: dict[str, str] = {
     "show_settings_transfer": "资金划转",
     "show_settings_export": "数据导出",
     "show_settings_password": "账户密码修改",
+    "show_settings_exchange_api": "交易所 API",
     "show_settings_options_swap": "期权币种兑换",
     "show_settings_options_transfer": "期权资金划转",
 }
@@ -118,6 +120,7 @@ def display_meta_for_ui() -> list[dict[str, Any]]:
         "show_nav_hedge_plan",
     ]
     settings_keys = [
+        "show_settings_exchange_api",
         "show_settings_transfer",
         "show_settings_export",
         "show_settings_password",