Enhance testing framework and UI feedback

- Updated architecture documentation to include details on UI rendering checks and Playwright end-to-end tests.
- Revised testing documentation to specify Playwright for frontend E2E tests and added details on running tests.
- Implemented feedback mechanism in scenario form for successful creation notifications.
- Added feedback div in ScenarioForm.html for user notifications.
- Created new fixtures for Playwright tests to manage server and browser instances.
- Developed comprehensive E2E tests for consumption, costs, equipment, maintenance, production, and scenarios.
- Added smoke tests to verify UI page loading and form submissions.
- Enhanced unit tests for simulation and validation, including new tests for report generation and validation errors.
- Created new test files for router validation to ensure consistent error handling.
- Established a new test suite for UI routes to validate dashboard and reporting functionalities.
- Implemented validation tests to ensure proper handling of JSON payloads.

tests/e2e/test_maintenance.py

@@ -0,0 +1,52 @@
+from uuid import uuid4
+
+from playwright.sync_api import Page, expect
+
+
+def test_maintenance_form_loads(page: Page):
+    """Verify the maintenance form page loads correctly."""
+    page.goto("/ui/maintenance")
+    expect(page).to_have_title("CalMiner Maintenance")
+    expect(page.locator("h1")).to_have_text("Maintenance")
+
+
+def test_create_maintenance_item(page: Page):
+    """Test creating a new maintenance item through the UI."""
+    # First, create a scenario and an equipment item.
+    page.goto("/ui/scenarios")
+    scenario_name = f"Maintenance Test Scenario {uuid4()}"
+    page.fill("input[name='name']", scenario_name)
+    page.click("button[type='submit']")
+    with page.expect_response("**/api/scenarios/"):
+        pass
+
+    page.goto("/ui/equipment")
+    equipment_name = f"Excavator EX-12 {uuid4()}"
+    page.select_option("select[name='scenario_id']", label=scenario_name)
+    page.fill("input[name='name']", equipment_name)
+    page.click("button[type='submit']")
+    with page.expect_response("**/api/equipment/"):
+        pass
+
+    # Now, navigate to the maintenance page and add an item.
+    page.goto("/ui/maintenance")
+
+    # Create a maintenance item.
+    maintenance_desc = "Scheduled engine overhaul"
+    page.select_option("select[name='scenario_id']", label=scenario_name)
+    page.select_option("select[name='equipment_id']", label=equipment_name)
+    page.fill("input[name='maintenance_date']", "2025-12-01")
+    page.fill("textarea[name='description']", maintenance_desc)
+    page.fill("input[name='cost']", "12000")
+    page.click("button[type='submit']")
+
+    with page.expect_response("**/api/maintenance/") as response_info:
+        pass
+    assert response_info.value.status == 201
+
+    # Verify the new item appears in the table.
+    expect(page.locator(f"tr:has-text('{maintenance_desc}')")).to_be_visible()
+
+    # Verify the feedback message.
+    expect(page.locator("#maintenance-feedback")
+           ).to_have_text("Maintenance entry saved.")