fix(webui): suppress empty queue copy on fetch failure (#458)

When Gitea credentials are missing or the queue fetch fails closed,
show "Not loaded" instead of "No open items." and keep pagination
marked unavailable. Successful empty inventories still show the empty
state with complete pagination proof.

Closes #458

tests/test_webui_queue_dashboard.py

@@ -12,12 +12,14 @@ from starlette.testclient import TestClient
 from webui.app import create_app
 from webui.queue_loader import (
     PaginationMeta,
+    QueueSnapshot,
     _classify_issue,
     _classify_pr,
     _extract_linked_issue,
     load_queue_snapshot,
     snapshot_to_dict,
 )
+from webui.queue_views import render_queue_page
 
 _RECENT = datetime.now(timezone.utc).isoformat()
 _STALE = (datetime.now(timezone.utc) - timedelta(days=30)).isoformat()
@@ -210,5 +212,77 @@ class TestQueueRoutes(unittest.TestCase):
         self.assertEqual(len(snapshot.prs), 0)
 
 
+def _empty_pagination() -> PaginationMeta:
+    return PaginationMeta(
+        page=1,
+        per_page=50,
+        returned_count=0,
+        has_more=False,
+        is_final_page=True,
+        inventory_complete=True,
+        pages_fetched=1,
+    )
+
+
+def _empty_fetch(*_args, **_kwargs):
+    return [], _empty_pagination()
+
+
+class TestQueueFailClosedUx(unittest.TestCase):
+    """Regression tests for #458 fail-closed empty-state copy."""
+
+    def test_fail_closed_view_suppresses_empty_queue_copy(self):
+        snapshot = QueueSnapshot(
+            project_id="gitea-tools",
+            repo_label="Scaled-Tech-Consulting/Gitea-Tools",
+            prs=(),
+            issues=(),
+            pr_pagination=None,
+            issue_pagination=None,
+            fetch_error="Gitea credentials unavailable for gitea.prgs.cc",
+        )
+        html = render_queue_page(snapshot)
+        self.assertIn("Queue unavailable", html)
+        self.assertIn("Not loaded", html)
+        self.assertNotIn("No open items.", html)
+        self.assertIn("pagination:</strong> unavailable", html)
+
+    def test_fail_closed_route_does_not_show_empty_queue_copy(self):
+        client = TestClient(create_app())
+        snapshot = load_queue_snapshot(
+            fetch_prs=_empty_fetch,
+            fetch_issues=_empty_fetch,
+        )
+        snapshot = QueueSnapshot(
+            project_id=snapshot.project_id,
+            repo_label=snapshot.repo_label,
+            prs=(),
+            issues=(),
+            pr_pagination=None,
+            issue_pagination=None,
+            fetch_error="Gitea credentials unavailable for gitea.prgs.cc",
+        )
+        with mock.patch("webui.app.load_queue_snapshot", return_value=snapshot):
+            response = client.get("/queue")
+        self.assertEqual(response.status_code, 200)
+        self.assertIn("Queue unavailable", response.text)
+        self.assertNotIn("No open items.", response.text)
+
+    def test_successful_empty_inventory_shows_empty_copy(self):
+        snapshot = load_queue_snapshot(
+            fetch_prs=_empty_fetch,
+            fetch_issues=_empty_fetch,
+        )
+        self.assertIsNone(snapshot.fetch_error)
+        self.assertEqual(len(snapshot.prs), 0)
+        self.assertEqual(len(snapshot.issues), 0)
+        self.assertTrue(snapshot.pr_pagination.inventory_complete)
+
+        html = render_queue_page(snapshot)
+        self.assertNotIn("Queue unavailable", html)
+        self.assertEqual(html.count("No open items."), 2)
+        self.assertIn("pagination (complete)", html)
+
+
 if __name__ == "__main__":
     unittest.main()