feat(e2e): add Playwright E2E test suite for critical user journeys (GRO-306)

Implements the automated Playwright E2E suite as the pre-UAT gate following
the UAT failures identified in GRO-299. Creates 5 test files in apps/web/e2e/:

- portal-auth.spec.ts: verifies client portal auth (client name shown, not "Hi, Guest")
- portal-data.spec.ts: verifies portal sections render without auth gates
- admin-services.spec.ts: asserts no duplicate service names in admin/services and booking wizard
- admin-reports.spec.ts: verifies reports page shows non-zero data for last 60 days
- console-health.spec.ts: asserts no 404s for favicon/PWA assets and no JS exceptions

Also adds:
- apps/web/e2e/ with Playwright config targeting groombook.dev.farh.net
- Shared fixtures with storageState-based auth via dev login selector
- test:e2e npm script in apps/web/package.json
- web-e2e CI job targeting PRs (runs after deploy-dev)

Note: Tests 1 & 2 (portal auth/data) depend on GRO-300 being deployed.
Tests 3-5 run against current dev state.

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

apps/web/e2e/package.json

@@ -0,0 +1,15 @@
+{
+  "name": "@groombook/web-e2e",
+  "version": "0.0.1",
+  "private": true,
+  "type": "module",
+  "scripts": {
+    "test": "playwright test",
+    "test:ui": "playwright test --ui",
+    "test:report": "playwright show-report"
+  },
+  "devDependencies": {
+    "@playwright/test": "^1.50.1"
+  },
+  "license": "AGPL-3.0-only"
+}