Add Stage 2.8 recall, quality gate, retries, and publish idempotency

tests/test_quality_gate.py

@@ -0,0 +1,78 @@
+import unittest
+
+from ai_daily_report.models import NewsItem, SourceResult
+from ai_daily_report.quality_gate import evaluate_quality_gate
+
+
+def news_item(item_id, title="Story"):
+    return NewsItem(
+        id=item_id,
+        source_group="AI HOT",
+        source_label="AI HOT",
+        source_role="primary",
+        source_priority=10,
+        title_raw=f"{title} {item_id}",
+        title_norm=f"{title} {item_id}".lower(),
+        summary_raw="summary",
+        url=f"https://example.com/{item_id}",
+        canonical_url=f"https://example.com/{item_id}",
+    )
+
+
+class QualityGateTests(unittest.TestCase):
+    def test_warns_when_stage3_candidates_zero_for_large_item_set(self):
+        items = [news_item(str(index)) for index in range(31)]
+        report = evaluate_quality_gate(
+            items,
+            source_results=[],
+            reports={"stage3": {"candidate_group_count": 0}},
+            config={"warn_when_stage3_candidates_zero_min_items": 30},
+        )
+
+        self.assertIn("stage3_candidates_zero", report["warnings"])
+        self.assertEqual(report["blocking_errors"], [])
+
+    def test_warns_on_enabled_source_failure(self):
+        report = evaluate_quality_gate(
+            [news_item("a")],
+            source_results=[
+                SourceResult(
+                    source="橘鸦AI早报",
+                    role="supplement",
+                    ok=False,
+                    status="error",
+                    error="HTTPError: 404",
+                )
+            ],
+            reports={"stage3": {"candidate_group_count": 1}},
+            config={"warn_on_enabled_source_failure": True},
+        )
+
+        self.assertIn("enabled_source_failed:橘鸦AI早报:error", report["warnings"])
+        self.assertEqual(report["source_failures"][0]["source"], "橘鸦AI早报")
+
+    def test_blocks_required_source_failure_when_configured(self):
+        report = evaluate_quality_gate(
+            [news_item("a")],
+            source_results=[
+                SourceResult(
+                    source="AI HOT",
+                    role="primary",
+                    ok=False,
+                    status="timeout",
+                    error="TimeoutError",
+                )
+            ],
+            reports={"stage3": {"candidate_group_count": 1}},
+            config={
+                "block_on_required_source_failure": True,
+                "required_sources": ["AI HOT"],
+            },
+        )
+
+        self.assertIn("required_source_failed:AI HOT:timeout", report["blocking_errors"])
+        self.assertTrue(report["quality_gate_failed"])
+
+
+if __name__ == "__main__":
+    unittest.main()