feat: beta API integration test suite — 85 new tests across 6 modules

Extends integration test coverage from 108 to 193 tests for the beta gate.

New test modules:
- test_query_api_extended.py (33 tests): documents, evidence, macro/competitive, ops/admin, agents, analytics
- test_registry_write_paths.py (16 tests): write paths, validation, duplicates, competitor/exposure CRUD
- test_risk_approval_lifecycle.py (8 tests): evaluation edge cases, full approval lifecycle
- test_trading_extended.py (12 tests): config round-trips, decision filtering, override validation
- test_cross_service_roundtrip.py (4 tests): cross-service data consistency
- test_error_handling.py (12 tests): 404s, 422s, empty states, health checks

Seed script extended with watchlists, approvals, lockouts, notifications,
ingestion runs, saved queries, and daily risk snapshots.

tests/integration/test_error_handling.py

@@ -0,0 +1,170 @@
+"""Integration tests for error handling and empty-state behavior across all services.
+
+Validates that all endpoints return structured JSON errors (not HTML or stack
+traces) and handle empty-state gracefully, so the frontend never receives
+unexpected response formats.
+"""
+
+import pytest
+
+pytestmark = pytest.mark.asyncio
+
+
+# ---------------------------------------------------------------------------
+# Empty list endpoints
+# ---------------------------------------------------------------------------
+
+
+class TestEmptyListEndpoints:
+    """List endpoints with no matching data return 200 with []."""
+
+    async def test_documents_empty_filter(self, query_client):
+        """GET /api/documents?ticker=ZZZZ — no matching docs returns 200 with list."""
+        resp = await query_client.get("/api/documents", params={"ticker": "ZZZZ"})
+        assert resp.status_code == 200
+        data = resp.json()
+        assert isinstance(data, list)
+        assert len(data) == 0
+
+
+# ---------------------------------------------------------------------------
+# Not-found detail endpoints
+# ---------------------------------------------------------------------------
+
+
+class TestNotFoundEndpoints:
+    """Detail endpoints with non-existent UUID return 404 with JSON body."""
+
+    async def test_query_api_document_not_found(self, query_client):
+        """GET /api/documents/{id} — 404 with JSON body."""
+        fake_id = "00000000-0000-4000-ffff-000000000099"
+        resp = await query_client.get(f"/api/documents/{fake_id}")
+        assert resp.status_code == 404
+        data = resp.json()
+        assert isinstance(data, dict)
+
+    async def test_registry_company_not_found(self, registry_client):
+        """GET /companies/{id} — 404 with JSON body."""
+        fake_id = "00000000-0000-4000-ffff-000000000099"
+        resp = await registry_client.get(f"/companies/{fake_id}")
+        assert resp.status_code == 404
+        data = resp.json()
+        assert isinstance(data, dict)
+
+    async def test_risk_approval_not_found(self, risk_client):
+        """GET /approvals/{id} — 404 with JSON body."""
+        fake_id = "00000000-0000-4000-ffff-000000000099"
+        resp = await risk_client.get(f"/approvals/{fake_id}")
+        assert resp.status_code == 404
+        data = resp.json()
+        assert isinstance(data, dict)
+
+
+# ---------------------------------------------------------------------------
+# Validation errors
+# ---------------------------------------------------------------------------
+
+
+class TestValidationErrors:
+    """Invalid JSON body returns 422 with validation details."""
+
+    async def test_invalid_company_body(self, registry_client):
+        """POST /companies — missing required fields returns 422."""
+        resp = await registry_client.post("/companies", json={})
+        assert resp.status_code == 422
+        data = resp.json()
+        assert isinstance(data, dict)
+        assert "detail" in data
+
+
+# ---------------------------------------------------------------------------
+# Trend projection edge case
+# ---------------------------------------------------------------------------
+
+
+class TestTrendProjectionNoProjection:
+    """Trend projection with no projection returns appropriate response (not 500)."""
+
+    async def test_trend_projection_nonexistent(self, query_client):
+        """GET /api/trends/{id}/projection — non-existent trend returns 404, not 500."""
+        fake_id = "00000000-0000-4000-ffff-000000000099"
+        resp = await query_client.get(f"/api/trends/{fake_id}/projection")
+        assert resp.status_code != 500
+        assert resp.status_code in (200, 404)
+
+
+# ---------------------------------------------------------------------------
+# Macro impacts empty state
+# ---------------------------------------------------------------------------
+
+
+class TestMacroImpactsEmpty:
+    """Macro impacts with no data returns 200 with empty impacts list."""
+
+    async def test_macro_impacts_no_data(self, query_client):
+        """GET /api/macro/impacts/ZZZZ — no impacts returns 200 with empty list."""
+        resp = await query_client.get("/api/macro/impacts/ZZZZ")
+        assert resp.status_code == 200
+        data = resp.json()
+        assert "impacts" in data
+        assert isinstance(data["impacts"], list)
+        assert len(data["impacts"]) == 0
+
+
+# ---------------------------------------------------------------------------
+# Health endpoints across all services
+# ---------------------------------------------------------------------------
+
+
+class TestAllServiceHealthEndpoints:
+    """All four service health endpoints return {"status": "ok"}."""
+
+    async def test_query_api_health(self, query_client):
+        """GET /health — query API."""
+        resp = await query_client.get("/health")
+        assert resp.status_code == 200
+        assert resp.json()["status"] == "ok"
+
+    async def test_registry_health(self, registry_client):
+        """GET /health — symbol registry."""
+        resp = await registry_client.get("/health")
+        assert resp.status_code == 200
+        assert resp.json()["status"] == "ok"
+
+    async def test_risk_health(self, risk_client):
+        """GET /health — risk engine."""
+        resp = await risk_client.get("/health")
+        assert resp.status_code == 200
+        assert resp.json()["status"] == "ok"
+
+    async def test_trading_health(self, trading_client):
+        """GET /health — trading engine."""
+        resp = await trading_client.get("/health")
+        assert resp.status_code == 200
+        assert resp.json()["status"] == "ok"
+
+
+# ---------------------------------------------------------------------------
+# Override order structured error
+# ---------------------------------------------------------------------------
+
+
+class TestOverrideStructuredError:
+    """Override order returns structured JSON error when Redis unavailable."""
+
+    async def test_override_structured_error(self, trading_client):
+        """POST /api/trading/override/order — structured error (not unhandled exception)."""
+        payload = {
+            "ticker": "AAPL",
+            "side": "buy",
+            "quantity": 1.0,
+            "order_type": "market",
+        }
+        resp = await trading_client.post("/api/trading/override/order", json=payload)
+        # Accept 202 (success) or structured error
+        assert resp.status_code in (200, 202, 400, 422, 503)
+        data = resp.json()
+        assert isinstance(data, dict)
+        # If 503, verify it's JSON not an unhandled exception
+        if resp.status_code == 503:
+            assert "detail" in data or "error" in data or "message" in data