fix(notifications): 飞书推送按传入的 max_attempts 退避与记日志

_post_feishu 的退避判断与最终 WARNING 仍用模块常量 _FEISHU_MAX_ATTEMPTS(3),
设置页「发送测试消息」传 max_attempts=1 时: 唯一一次失败后仍 sleep 1 秒才返回,
日志写「已重试 3 次」而实际只试了 1 次。两处改用 max_attempts; 生产路径不变。

测试: 单次尝试不退避且日志计数为 1 (未修复时失败), 默认 3 次仍退避 1s、2s。

backend/tests/test_notification_adapters.py

@@ -3,6 +3,7 @@ from __future__ import annotations
 import hashlib
 import hmac
 import json
+import logging
 
 from app.services import email_adapter, webhook_adapter
 
@@ -98,3 +99,42 @@ def test_email_adapter_uses_starttls_login_and_multiple_recipients(monkeypatch):
     assert message["To"] == "one@example.com, two@example.com"
     assert message["Subject"] == "监控告警"
     assert smtp.calls[-1] == ("quit",)
+
+
+def _unreachable(*_args, **_kwargs):
+    raise ConnectionError("unreachable")
+
+
+def test_feishu_single_attempt_returns_without_backoff_and_logs_the_real_count(monkeypatch, caplog):
+    # 设置页「发送测试消息」传 max_attempts=1: 失败即返回, 不等退避, 日志计数如实。
+    sleeps: list[float] = []
+    monkeypatch.setattr(webhook_adapter.time, "sleep", lambda seconds: sleeps.append(seconds))
+    monkeypatch.setattr("httpx.post", _unreachable)
+    with caplog.at_level(logging.WARNING, logger=webhook_adapter.__name__):
+        ok = webhook_adapter.send_feishu(
+            "https://open.feishu.cn/open-apis/bot/v2/hook/abc", "标题", "正文", max_attempts=1
+        )
+    assert ok is False
+    assert sleeps == []
+    assert "已重试 1 次" in caplog.text
+
+
+def test_feishu_production_retries_keep_backoff(monkeypatch, caplog):
+    # 生产路径 (默认 3 次) 的退避与日志不变: 1s、2s 两次退避, 日志写 3 次。
+    sleeps: list[float] = []
+    calls = {"n": 0}
+
+    def unreachable(*_args, **_kwargs):
+        calls["n"] += 1
+        raise ConnectionError("unreachable")
+
+    monkeypatch.setattr(webhook_adapter.time, "sleep", lambda seconds: sleeps.append(seconds))
+    monkeypatch.setattr("httpx.post", unreachable)
+    with caplog.at_level(logging.WARNING, logger=webhook_adapter.__name__):
+        ok = webhook_adapter.send_feishu(
+            "https://open.feishu.cn/open-apis/bot/v2/hook/abc", "标题", "正文"
+        )
+    assert ok is False
+    assert calls["n"] == 3
+    assert sleeps == [1, 2]
+    assert "已重试 3 次" in caplog.text