feat(e2e): add E2E test infrastructure to headlamp-tns-csi-plugin

- Add e2e/auth.setup.ts for Headlamp authentication
- Add e2e/tns-csi.spec.ts smoke tests for TNS CSI plugin sidebar, navigation, and settings
- Add playwright.config.ts with Chromium project and setup dependency
- Add scripts/deploy-e2e-headlamp.sh for E2E Headlamp deployment
- Add scripts/teardown-e2e-headlamp.sh for E2E cleanup
- Add @playwright/test and e2e/e2e:headed npm scripts to package.json

Refs: PRI-697, PRI-698, PRI-639
Co-Authored-By: Paperclip <noreply@paperclip.ing>

package.json

@@ -23,7 +23,9 @@
     "format": "prettier --write src/",
     "format:check": "prettier --check src/",
     "test": "vitest run",
-    "test:watch": "vitest"
+    "test:watch": "vitest",
+    "e2e": "playwright test",
+    "e2e:headed": "playwright test --headed"
   },
   "peerDependencies": {
     "react": "^18.0.0",
@@ -46,7 +48,8 @@
     "react-dom": "^18.3.1",
     "react-router-dom": "^5.3.0",
     "typescript": "~5.6.2",
-    "vitest": "^3.2.4"
+    "vitest": "^3.2.4",
+    "@playwright/test": "^1.58.2"
   },
   "overrides": {
     "tar": "^7.5.11",