Test/add e2e and unit testing (#1282)

* feat: add string utility tests and vitest browser configuration

* feat: add Playwright for end-to-end testing and update snapshots

- Introduced Playwright for E2E testing with a new configuration file.
- Added test scripts to package.json for running E2E tests.
- Updated package-lock.json and package.json with new dependencies for Playwright and types.
- Created new SVG snapshot files for various layers (ruler, scaleBar, temperature, terrain, vignette, zones) to support visual testing.
- Excluded e2e directory from TypeScript compilation.

* Apply suggestions from code review

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

* Add SVG layer snapshots for various components

- Added ruler layer snapshot with hidden display.
- Added scale bar layer snapshot with detailed structure and styling.
- Added temperature layer snapshot with opacity and stroke settings.
- Added terrain layer snapshot with ocean and land heights groups.
- Added vignette layer snapshot with mask and opacity settings.
- Added zones layer snapshot with specified opacity and stroke settings.

* fix: update Playwright browser installation command to use npx

* Update snapshots

* refactor: remove unused layer tests and their corresponding snapshots as fonts are unpredictable

---------

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

vitest.browser.config.ts

@@ -0,0 +1,18 @@
+import { defineConfig } from 'vitest/config'
+import { playwright } from '@vitest/browser-playwright'
+
+export default defineConfig({
+  test: {
+    browser: {
+      enabled: true,
+      provider: playwright(),
+      // https://vitest.dev/config/browser/playwright
+      instances: [
+        { name: 'chromium', browser: 'chromium' },
+      ],
+      locators: {
+        testIdAttribute: 'id',
+      },
+    },
+  },
+})