feat(L+M): configurable dashboard widget system + test framework

Phase L: Dashboard widget system
- Migration 046: dashboard_configs table (user/tenant/role fallback cascade)
- DashboardConfig model + dashboard_service with get/upsert per-user and tenant-default
- API router: GET/PUT /api/dashboard/config, GET/PUT /api/dashboard/tenant-default
- Frontend: 5 widget components (ProductionStats, QueueStatus, RecentRenders, CostOverview, WorkerStatus)
- DashboardGrid with API-backed config, DashboardCustomizeModal (checkbox selection, save/cancel)
- Dashboard.tsx: widget grid + analytics section (privileged users)
- Admin.tsx: restructured with new section order and Maintenance 2-col grid

Phase M: Test framework
- Backend: pytest-asyncio + pytest-cov + factory-boy in pyproject.toml
- conftest.py: excel_dir fixtures + async DB fixtures + mock storage/celery stubs
- Domain tests: billing_service, cache_service, notifications_service, imports_sanity
- Integration: test_api_health.py smoke test (requires running backend)
- Frontend: vitest + @testing-library/react + msw added to package.json
- vite.config.ts: test block (jsdom + globals + setupFiles)
- tsconfig.json: exclude src/__tests__ from main tsc (test runner handles its own types)
- MSW handlers for /api/auth/me, Billing.test.tsx, formatters.test.ts

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/tests/domains/test_billing_service.py

@@ -0,0 +1,33 @@
+"""Tests for billing service."""
+import pytest
+from app.domains.billing.service import create_invoice, get_invoices
+
+
+@pytest.mark.asyncio
+async def test_create_invoice_minimal(db, admin_user):
+    """Invoice kann mit Mindestdaten erstellt werden."""
+    invoice = await create_invoice(
+        db,
+        tenant_id=None,
+        order_line_ids=[],
+        notes="Test invoice",
+    )
+    assert invoice.id is not None
+    assert invoice.invoice_number.startswith("INV-")
+    assert invoice.status == "draft"
+    assert invoice.currency == "EUR"
+
+
+@pytest.mark.asyncio
+async def test_invoice_number_sequential(db, admin_user):
+    """Invoice-Nummern sind sequenziell und eindeutig."""
+    inv1 = await create_invoice(db, tenant_id=None, order_line_ids=[], notes="First")
+    inv2 = await create_invoice(db, tenant_id=None, order_line_ids=[], notes="Second")
+    assert inv1.invoice_number != inv2.invoice_number
+
+
+@pytest.mark.asyncio
+async def test_get_invoices_returns_list(db):
+    """get_invoices gibt eine Liste zurück."""
+    invoices = await get_invoices(db, tenant_id=None)
+    assert isinstance(invoices, list)

backend/tests/domains/test_cache_service.py

@@ -0,0 +1,41 @@
+"""Tests for STL conversion cache service (pure/unit — no DB needed)."""
+import pytest
+from pathlib import Path
+from app.domains.products.cache_service import compute_step_hash, _cache_key
+
+
+def test_compute_step_hash_stable(tmp_path):
+    """Gleiche Datei → gleicher Hash."""
+    f = tmp_path / "test.stp"
+    f.write_bytes(b"STEP data content")
+    h1 = compute_step_hash(str(f))
+    h2 = compute_step_hash(str(f))
+    assert h1 == h2
+    assert len(h1) == 64  # SHA256 hex
+
+
+def test_compute_step_hash_differs(tmp_path):
+    """Andere Datei → anderer Hash."""
+    f1 = tmp_path / "a.stp"
+    f1.write_bytes(b"content A")
+    f2 = tmp_path / "b.stp"
+    f2.write_bytes(b"content B")
+    assert compute_step_hash(str(f1)) != compute_step_hash(str(f2))
+
+
+def test_cache_key_format():
+    """Cache-Key hat korrektes Format."""
+    key = _cache_key("abc123", "low")
+    assert key == "conversion-cache/abc123_low.stl"
+
+
+def test_store_stl_cache_uses_path(tmp_path, mock_storage):
+    """store_stl_cache übergibt Path-Objekt an storage.upload."""
+    from app.domains.products.cache_service import store_stl_cache
+    stl = tmp_path / "test.stl"
+    stl.write_bytes(b"fake stl")
+    store_stl_cache("abc123", "low", str(stl))
+    call_args = mock_storage.upload.call_args
+    assert call_args is not None
+    first_arg = call_args[0][0]
+    assert isinstance(first_arg, Path), f"Expected Path, got {type(first_arg)}"

backend/tests/domains/test_imports_sanity.py

@@ -0,0 +1,28 @@
+"""Tests for Excel sanity check service (sync Celery service).
+
+Note: run_sanity_check opens a real synchronous DB connection, so the
+meaningful tests are integration-only (marked accordingly). The unit-level
+test only verifies the import and signature.
+"""
+import pytest
+
+
+def test_run_sanity_check_importable():
+    """run_sanity_check can be imported without errors."""
+    from app.domains.imports.service import run_sanity_check
+    assert callable(run_sanity_check)
+
+
+@pytest.mark.integration
+def test_run_sanity_check_missing_file_does_not_crash():
+    """Sanity-check-Service gibt leeres Dict zurück bei nicht existierendem File (integration)."""
+    from app.domains.imports.service import run_sanity_check
+    import uuid
+    import app.models  # noqa - register all models so SQLAlchemy relationships resolve
+    result = run_sanity_check(
+        validation_id=str(uuid.uuid4()),
+        excel_path="/nonexistent/test.xlsx",
+        tenant_id=None,
+    )
+    # Service returns {} when validation not found
+    assert isinstance(result, dict)

backend/tests/domains/test_notifications_service.py

@@ -0,0 +1,27 @@
+"""Tests for notification config service."""
+import pytest
+from app.domains.notifications.service import (
+    upsert_notification_config,
+    get_notification_configs,
+)
+
+
+@pytest.mark.asyncio
+async def test_upsert_creates_config(db, admin_user):
+    """Kann Notification-Config anlegen."""
+    await upsert_notification_config(db, admin_user.id, "render_complete", "in_app", True)
+    configs = await get_notification_configs(db, admin_user.id)
+    assert len(configs) >= 1
+    render_cfg = next((c for c in configs if c.event_type == "render_complete"), None)
+    assert render_cfg is not None
+
+
+@pytest.mark.asyncio
+async def test_upsert_updates_existing(db, admin_user):
+    """Update überschreibt bestehende Config."""
+    await upsert_notification_config(db, admin_user.id, "order_submitted", "in_app", True)
+    await upsert_notification_config(db, admin_user.id, "order_submitted", "in_app", False)
+    configs = await get_notification_configs(db, admin_user.id)
+    cfg = next((c for c in configs if c.event_type == "order_submitted"), None)
+    assert cfg is not None
+    assert cfg.enabled is False