fix(ai): DeepSeek 余额按官方 balance_infos 解析

/user/balance 返回的是 {is_available, balance_infos[]}，没有顶层 data，
旧实现永远解析出 None，连接测试会显示「余额 None CNY」。同时补全
TotHost 预设平台，新环境初始化后即可直接配 whmcs-panel。

tests/test_adapters.py

@@ -212,17 +212,47 @@ def test_registry_get_adapter_routing():
 
 # --------------------------- AI 平台适配器 --------------------------- #
 def test_deepseek_balance_normalization():
+    """官方 /user/balance 返回 balance_infos，不是顶层 data"""
     adapter = DeepSeekAdapter({"api_key": "x"})
-    mock = {"data": {"total_balance": "88.50", "granted_balance": "10.00"}}
+    mock = {
+        "is_available": True,
+        "balance_infos": [{
+            "currency": "CNY",
+            "total_balance": "88.50",
+            "granted_balance": "10.00",
+            "topped_up_balance": "78.50",
+        }],
+    }
     with patch.object(DeepSeekAdapter, "_get", return_value=mock):
         acc = adapter.get_account()
     assert acc.balance == 88.5  # 字符串 -> float
     assert acc.currency == "CNY"
 
 
+def test_deepseek_balance_prefers_cny_when_multiple():
+    adapter = DeepSeekAdapter({"api_key": "x"})
+    mock = {"balance_infos": [
+        {"currency": "USD", "total_balance": "1.00"},
+        {"currency": "CNY", "total_balance": "7.20"},
+    ]}
+    with patch.object(DeepSeekAdapter, "_get", return_value=mock):
+        acc = adapter.get_account()
+    assert acc.balance == 7.2
+    assert acc.currency == "CNY"
+
+
+def test_deepseek_balance_supports_legacy_shape():
+    """兼容旧响应 data.total_balance，避免上线后旧 mock/代理失效"""
+    adapter = DeepSeekAdapter({"api_key": "x"})
+    with patch.object(DeepSeekAdapter, "_get", return_value={"data": {"total_balance": "5.00"}}):
+        acc = adapter.get_account()
+    assert acc.balance == 5.0
+
+
 def test_deepseek_test_connection_includes_balance():
     adapter = DeepSeekAdapter({"api_key": "x"})
-    with patch.object(DeepSeekAdapter, "_get", return_value={"data": {"total_balance": "88.50"}}):
+    mock = {"balance_infos": [{"currency": "CNY", "total_balance": "88.50"}]}
+    with patch.object(DeepSeekAdapter, "_get", return_value=mock):
         result = adapter.test_connection()
     assert result["ok"] is True
     assert "88.5" in result["message"]