feat: UI polish - dark default, version drift vs default release, humanized enums, failed-jobs layout, processing button hierarchy, PT-BR titles/CTAs

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

central/tests/test_operational_view_models.py

@@ -564,3 +564,13 @@ def test_blocker_breakdown_query_groups_on_same_postgres_expression():
 
     assert "GROUP BY blocked_products.field" in sql
     assert "GROUP BY coalesce" not in sql
+
+
+def test_remaining_technical_enums_have_human_labels():
+    from central.app.panel_presentation import health_reason_label
+    assert blocker_reason_label("INVALID_NCM") == "NCM inválido"
+    assert blocker_reason_label("LEGACY_NCM") == "NCM legado"
+    assert blocker_type_label("BLOCKED_MISSING_EVIDENCE") == "Evidência fiscal ausente"
+    assert health_reason_label("last heartbeat exceeds 300s") == "Sem heartbeat recente"
+    assert health_reason_label("persistent technical failure") == "Falha técnica persistente"
+    assert blocker_reason_label("SOMETHING_NEW") == "Something new"  # unknown codes degrade readably, never crash