Add comprehensive automated testing infrastructure

Backend:
  - pytest configuration with async support and coverage
  - Unit tests for notification service (23 tests)
  - Unit tests for smart plug manager (12 tests)
  - Unit tests for archive service (16 tests)
  - Integration tests for API endpoints
  - Fix: notifications now send immediately (digest is summary only)

  Frontend:
  - Vitest configuration with jsdom and coverage
  - MSW for API mocking
  - Component tests for Toggle, Button, Card, ConfirmModal (77 tests)
  - Test utilities with custom render wrapper

  CI/CD:
  - GitHub Actions workflow for automated testing
  - Backend lint, unit tests, integration tests
  - Frontend lint, type-check, unit tests, build

backend/tests/integration/test_archives_api.py

@@ -0,0 +1,294 @@
+"""Integration tests for Archives API endpoints.
+
+Tests the full request/response cycle for /api/v1/archives/ endpoints.
+"""
+
+import pytest
+from httpx import AsyncClient
+
+
+class TestArchivesAPI:
+    """Integration tests for /api/v1/archives/ endpoints."""
+
+    # ========================================================================
+    # List endpoints
+    # ========================================================================
+
+    @pytest.mark.asyncio
+    @pytest.mark.integration
+    async def test_list_archives_empty(self, async_client: AsyncClient):
+        """Verify empty list is returned when no archives exist."""
+        response = await async_client.get("/api/v1/archives/")
+
+        assert response.status_code == 200
+        data = response.json()
+        assert isinstance(data, list)
+        assert len(data) == 0
+
+    @pytest.mark.asyncio
+    @pytest.mark.integration
+    async def test_list_archives_with_data(
+        self, async_client: AsyncClient, archive_factory, printer_factory, db_session
+    ):
+        """Verify list returns existing archives."""
+        printer = await printer_factory()
+        await archive_factory(printer.id, print_name="Test Archive")
+
+        response = await async_client.get("/api/v1/archives/")
+
+        assert response.status_code == 200
+        data = response.json()
+        assert isinstance(data, list)
+        assert len(data) >= 1
+        assert any(a["print_name"] == "Test Archive" for a in data)
+
+    @pytest.mark.asyncio
+    @pytest.mark.integration
+    async def test_list_archives_pagination(
+        self, async_client: AsyncClient, archive_factory, printer_factory, db_session
+    ):
+        """Verify pagination works correctly."""
+        printer = await printer_factory()
+        # Create 5 archives
+        for i in range(5):
+            await archive_factory(printer.id, print_name=f"Archive {i}")
+
+        # Get first page with limit 2
+        response = await async_client.get("/api/v1/archives/?limit=2&offset=0")
+
+        assert response.status_code == 200
+        data = response.json()
+        assert isinstance(data, list)
+        assert len(data) == 2
+
+    @pytest.mark.asyncio
+    @pytest.mark.integration
+    async def test_list_archives_filter_by_printer(
+        self, async_client: AsyncClient, archive_factory, printer_factory, db_session
+    ):
+        """Verify filtering by printer_id works."""
+        printer1 = await printer_factory(name="Printer 1", serial_number="00M09A000000001")
+        printer2 = await printer_factory(name="Printer 2", serial_number="00M09A000000002")
+        await archive_factory(printer1.id, print_name="Printer 1 Archive")
+        await archive_factory(printer2.id, print_name="Printer 2 Archive")
+
+        response = await async_client.get(
+            f"/api/v1/archives/?printer_id={printer1.id}"
+        )
+
+        assert response.status_code == 200
+        data = response.json()
+        assert all(a["printer_id"] == printer1.id for a in data)
+
+    # ========================================================================
+    # Get single endpoint
+    # ========================================================================
+
+    @pytest.mark.asyncio
+    @pytest.mark.integration
+    async def test_get_archive(
+        self, async_client: AsyncClient, archive_factory, printer_factory, db_session
+    ):
+        """Verify single archive can be retrieved."""
+        printer = await printer_factory()
+        archive = await archive_factory(printer.id, print_name="Get Test Archive")
+
+        response = await async_client.get(f"/api/v1/archives/{archive.id}")
+
+        assert response.status_code == 200
+        result = response.json()
+        assert result["id"] == archive.id
+        assert result["print_name"] == "Get Test Archive"
+
+    @pytest.mark.asyncio
+    @pytest.mark.integration
+    async def test_get_archive_not_found(self, async_client: AsyncClient):
+        """Verify 404 for non-existent archive."""
+        response = await async_client.get("/api/v1/archives/9999")
+
+        assert response.status_code == 404
+
+    # ========================================================================
+    # Update endpoints
+    # ========================================================================
+
+    @pytest.mark.asyncio
+    @pytest.mark.integration
+    async def test_update_archive_name(
+        self, async_client: AsyncClient, archive_factory, printer_factory, db_session
+    ):
+        """Verify archive name can be updated."""
+        printer = await printer_factory()
+        archive = await archive_factory(printer.id, print_name="Original Name")
+
+        response = await async_client.patch(
+            f"/api/v1/archives/{archive.id}",
+            json={"print_name": "Updated Name"}
+        )
+
+        assert response.status_code == 200
+        assert response.json()["print_name"] == "Updated Name"
+
+    @pytest.mark.asyncio
+    @pytest.mark.integration
+    async def test_update_archive_notes(
+        self, async_client: AsyncClient, archive_factory, printer_factory, db_session
+    ):
+        """Verify archive notes can be updated."""
+        printer = await printer_factory()
+        archive = await archive_factory(printer.id)
+
+        response = await async_client.patch(
+            f"/api/v1/archives/{archive.id}",
+            json={"notes": "Great print!"}
+        )
+
+        assert response.status_code == 200
+        assert response.json()["notes"] == "Great print!"
+
+    @pytest.mark.asyncio
+    @pytest.mark.integration
+    async def test_update_archive_favorite(
+        self, async_client: AsyncClient, archive_factory, printer_factory, db_session
+    ):
+        """Verify archive favorite status can be updated."""
+        printer = await printer_factory()
+        archive = await archive_factory(printer.id)
+
+        response = await async_client.patch(
+            f"/api/v1/archives/{archive.id}",
+            json={"is_favorite": True}
+        )
+
+        assert response.status_code == 200
+        assert response.json()["is_favorite"] is True
+
+    # ========================================================================
+    # Delete endpoints
+    # ========================================================================
+
+    @pytest.mark.asyncio
+    @pytest.mark.integration
+    async def test_delete_archive(
+        self, async_client: AsyncClient, archive_factory, printer_factory, db_session
+    ):
+        """Verify archive can be deleted."""
+        printer = await printer_factory()
+        archive = await archive_factory(printer.id)
+        archive_id = archive.id
+
+        response = await async_client.delete(f"/api/v1/archives/{archive_id}")
+
+        assert response.status_code == 200
+
+        # Verify deleted
+        response = await async_client.get(f"/api/v1/archives/{archive_id}")
+        assert response.status_code == 404
+
+    @pytest.mark.asyncio
+    @pytest.mark.integration
+    async def test_delete_nonexistent_archive(self, async_client: AsyncClient):
+        """Verify deleting non-existent archive returns 404."""
+        response = await async_client.delete("/api/v1/archives/9999")
+
+        assert response.status_code == 404
+
+    # ========================================================================
+    # Statistics endpoints
+    # ========================================================================
+
+    @pytest.mark.asyncio
+    @pytest.mark.integration
+    async def test_get_archive_stats(
+        self, async_client: AsyncClient, archive_factory, printer_factory, db_session
+    ):
+        """Verify archive statistics can be retrieved."""
+        printer = await printer_factory()
+        await archive_factory(
+            printer.id,
+            status="completed",
+            print_time_seconds=3600,
+            filament_used_grams=50.0,
+        )
+        await archive_factory(
+            printer.id,
+            status="completed",
+            print_time_seconds=7200,
+            filament_used_grams=100.0,
+        )
+
+        response = await async_client.get("/api/v1/archives/stats")
+
+        assert response.status_code == 200
+        result = response.json()
+        # Check for actual stats fields
+        assert "total_prints" in result
+        assert "successful_prints" in result
+
+
+class TestArchiveDataIntegrity:
+    """Tests for archive data integrity."""
+
+    @pytest.mark.asyncio
+    @pytest.mark.integration
+    async def test_archive_linked_to_printer(
+        self, async_client: AsyncClient, archive_factory, printer_factory, db_session
+    ):
+        """Verify archive is properly linked to printer."""
+        printer = await printer_factory(name="My Printer")
+        archive = await archive_factory(printer.id)
+
+        response = await async_client.get(f"/api/v1/archives/{archive.id}")
+
+        assert response.status_code == 200
+        result = response.json()
+        assert result["printer_id"] == printer.id
+
+    @pytest.mark.asyncio
+    @pytest.mark.integration
+    async def test_archive_stores_print_data(
+        self, async_client: AsyncClient, archive_factory, printer_factory, db_session
+    ):
+        """Verify archive stores all print data correctly."""
+        printer = await printer_factory()
+        archive = await archive_factory(
+            printer.id,
+            print_name="Test Print",
+            filename="test.3mf",
+            status="completed",
+            filament_type="PLA",
+            filament_used_grams=75.5,
+            print_time_seconds=5400,
+        )
+
+        response = await async_client.get(f"/api/v1/archives/{archive.id}")
+
+        assert response.status_code == 200
+        result = response.json()
+        assert result["print_name"] == "Test Print"
+        assert result["filename"] == "test.3mf"
+        assert result["status"] == "completed"
+        assert result["filament_type"] == "PLA"
+        assert result["filament_used_grams"] == 75.5
+        assert result["print_time_seconds"] == 5400
+
+    @pytest.mark.asyncio
+    @pytest.mark.integration
+    async def test_archive_update_persists(
+        self, async_client: AsyncClient, archive_factory, printer_factory, db_session
+    ):
+        """CRITICAL: Verify archive updates persist."""
+        printer = await printer_factory()
+        archive = await archive_factory(printer.id, notes="Original notes")
+
+        # Update
+        await async_client.patch(
+            f"/api/v1/archives/{archive.id}",
+            json={"notes": "Updated notes", "is_favorite": True}
+        )
+
+        # Verify persistence
+        response = await async_client.get(f"/api/v1/archives/{archive.id}")
+        result = response.json()
+        assert result["notes"] == "Updated notes"
+        assert result["is_favorite"] is True