feat(api): DeepSeek V4 Flash 默认、HTTP 错讯与多供应商分层

- 主链路默认 deepseek-v4-flash，DEEPSEEK_THINKING_ENABLED 对齐旧非思考 chat
- 评测台评审装配迁入 adapters/llm（deepseek_eval_judge、zhipu_eval_judge）与 eval_judge_spec
- 拆分 llm_http_openai_chat_errors 与 llm_errors（DeepSeek/智谱品牌与文档链），llm_call 支持 http_error_vendor
- EvalJudgeService 按 spec.provider 传入 allm_json_call；评测台前端文案改为 V4 Flash
- 更新 .env 示例与 staging/production 的 DEEPSEEK_MODEL；补充 openai/供应商错讯测试

Made-with: Cursor

api/tests/test_openai_compatible_errors.py

@@ -0,0 +1,68 @@
+"""传输层 `llm_http_openai_chat_errors` 的中性错讯；兼容 re-export 仍经 openai_compatible_errors。"""
+
+import httpx
+import pytest
+from openai import APIStatusError
+
+from app.core.openai_compatible_errors import (
+    extract_openai_http_status,
+    format_openai_compatible_http_error_message,
+    should_log_openai_error_as_warning,
+)
+
+
+def _status_error(status: int, *, body: object | None = None) -> APIStatusError:
+    req = httpx.Request("POST", "https://api.deepseek.com/v1/chat/completions")
+    resp = httpx.Response(status, request=req, json=body if body is not None else {})
+    return APIStatusError("upstream", response=resp, body=body)
+
+
+def test_extract_status_from_api_status_error() -> None:
+    e = _status_error(429)
+    assert extract_openai_http_status(e) == 429
+
+
+def test_format_402_balance_chinese_message() -> None:
+    e = _status_error(
+        402,
+        body={"error": {"message": "Insufficient balance", "type": "insufficient_quota"}},
+    )
+    msg = format_openai_compatible_http_error_message(e)
+    assert msg is not None
+    assert "402" in msg
+    assert "余额" in msg
+
+
+def test_format_401_and_warning_flag() -> None:
+    e = _status_error(401, body={"error": {"message": "invalid api key"}})
+    assert should_log_openai_error_as_warning(e) is True
+    m = format_openai_compatible_http_error_message(e)
+    assert m is not None
+    assert "401" in m
+    assert "密钥" in m
+
+
+def test_format_503_server_busy() -> None:
+    e = _status_error(503)
+    m = format_openai_compatible_http_error_message(e)
+    assert m is not None
+    assert "503" in m
+    assert should_log_openai_error_as_warning(e) is False
+
+
+def test_format_httpx_http_status_error() -> None:
+    req = httpx.Request("GET", "https://api.deepseek.com/v1/models")
+    resp = httpx.Response(429, request=req)
+    try:
+        resp.raise_for_status()
+    except httpx.HTTPStatusError as e:
+        m = format_openai_compatible_http_error_message(e)
+        assert m is not None
+        assert "429" in m
+
+
+def test_unknown_status_418() -> None:
+    e = _status_error(418)
+    m = format_openai_compatible_http_error_message(e)
+    assert m is not None
+    assert "418" in m