Added data-quality health checks.

tests/test_data_quality.py

@@ -0,0 +1,8 @@
+import unittest
+from fgai.data_quality import assess_data_quality
+from fgai.logs import parse_log_line
+
+class DataQualityTests(unittest.TestCase):
+    def test_reports_missing_source_and_timestamp(self):
+        quality = assess_data_quality([parse_log_line("srcip=10.0.0.1 timestamp=now"), parse_log_line("action=deny")], {})
+        self.assertEqual(quality["missing_source"], 1)