Refactor AI daily report pipeline

tests/test_validate.py

@@ -0,0 +1,14 @@
+import unittest
+
+from ai_daily_report.validate import validate_report_markdown
+
+
+class ValidateTests(unittest.TestCase):
+    def test_validate_report_markdown_delegates_markdown_checks(self):
+        report = validate_report_markdown("", [])
+
+        self.assertIn("no_items", report["blocking_errors"])
+
+
+if __name__ == "__main__":
+    unittest.main()