feat: 新增企微 Delta 模式相关配置读取函数

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

tests/test_wecom_delta.py

@@ -0,0 +1,42 @@
+"""Tests for WeCom delta mode."""
+
+from __future__ import annotations
+
+import os
+import unittest
+from unittest.mock import patch
+
+from daily.config import (
+    delta_baseline_fallback,
+    env_bool,
+    force_push,
+    news_dedup_days,
+    skip_push_when_silent,
+    wecom_mode,
+)
+
+
+class ConfigHelpersTests(unittest.TestCase):
+    def test_wecom_mode_defaults_delta(self):
+        with patch.dict(os.environ, {}, clear=True):
+            self.assertEqual(wecom_mode(), "delta")
+
+    def test_wecom_mode_full(self):
+        with patch.dict(os.environ, {"DAILY_WECOM_MODE": "full"}, clear=True):
+            self.assertEqual(wecom_mode(), "full")
+
+    def test_env_bool_truthy(self):
+        with patch.dict(os.environ, {"DAILY_FORCE_PUSH": "1"}, clear=True):
+            self.assertTrue(env_bool("DAILY_FORCE_PUSH", False))
+
+    def test_skip_push_when_silent_default(self):
+        with patch.dict(os.environ, {}, clear=True):
+            self.assertTrue(skip_push_when_silent())
+
+    def test_news_dedup_days_default(self):
+        with patch.dict(os.environ, {}, clear=True):
+            self.assertEqual(news_dedup_days(), 7)
+
+    def test_delta_baseline_fallback_default(self):
+        with patch.dict(os.environ, {}, clear=True):
+            self.assertEqual(delta_baseline_fallback(), "full")