Remove all E2E infrastructure — approach is dead

Delete the entire local E2E testing setup:
- e2e/ directory (Playwright tests)
- scripts/deploy-e2e-headlamp.sh and teardown-e2e-headlamp.sh
- .github/workflows/e2e.yaml
- playwright.config.ts
- E2E npm scripts and @playwright/test dependency
- E2E-related .gitignore entries

RBAC is managed by Flux GitOps in privilegedescalation/infra.

Co-Authored-By: Paperclip <noreply@paperclip.ing>

package.json

@@ -22,9 +22,7 @@
     "format": "prettier --write src/",
     "format:check": "prettier --check src/",
     "test": "vitest run",
-    "test:watch": "vitest",
-    "e2e": "playwright test",
-    "e2e:headed": "playwright test --headed"
+    "test:watch": "vitest"
   },
   "peerDependencies": {
     "react": "^18.0.0",
@@ -32,7 +30,6 @@
   },
   "devDependencies": {
     "@kinvolk/headlamp-plugin": "^0.13.0",
-    "@playwright/test": "^1.58.2",
     "@testing-library/jest-dom": "^6.4.8",
     "@testing-library/react": "^16.0.0",
     "@testing-library/user-event": "^14.5.2",