test: Add new Overview page UI tests and update login flow

[emmaaroche]

Description

• Added UI tests for the console plugin Overview page
• Implemented page objects following the navigator pattern for Overview page resources (Gateways, HTTPRoutes, and Policies)
• Refactored UI tests to share login authentication across all UI tests
• Refactored UI test's client to have a longer connect timeout time to fix errors occurring in nightlies

Closes #839

UI test issue: #556

Changes

Tests

• test_getting_started_section: Verifies all Getting Started resource cards and documentation links are present and correct
• test_gateways_section: Validates Gateway status metrics (Total, Healthy, Unhealthy) are displayed
• test_gateways_analysis_section: Creates Gateway via UI, verifies metrics update and Gateway becomes healthy, then deletes it
• test_policies_section: Creates policy via UI, verifies it appears in overview and enforces correctly, then deletes it (uses RateLimitPolicy as sample since other policies tested separately)
• test_httproute_section: Creates HTTPRoute via UI, verifies it appears in overview, then deletes it

New Features

• Page Objects: Implemented OverviewPage, GatewayNewPageYaml, HTTPRouteNewPageYaml, and PolicyDetailsPage for CRUD support
• Base Resource Class: Created BaseResourceNewPageYaml base class providing shared editor interaction and delete functionality

Refactoring

• Login/Authentication Optimization: Implemented Playwright storage state pattern to login once per test session and reuse authentication across all UI tests, significantly reducing test execution time
• Shared Conftest: Moved conftest.py from policies/ to parent console_plugin/ directory to share authentication state across all UI tests

Verification steps

Run the new Overview page tests:

poetry run pytest -vv -n4 testsuite/tests/singlecluster/ui/console_plugin/overview/test_overview.py

Run all UI tests to verify shared conftest changes don't break existing policy tests:

make ui

Run using the UI Container test image:

docker run --rm \
    -v /tmp/ocp/kubeconfig.kua-420-2:/run/kubeconfig:ro \
    -v $(pwd)/config/settings.local.yaml:/run/secrets.yaml:ro \
    -v $(pwd)/test-run-results:/test-run-results \
    quay.io/rh-ee-eroche/testsuite-ui:unstable