test(e2e) : initialise la suite Playwright (login + sidebar RBAC)

- 11 tests couvrant le login (3) et la visibilite sidebar par RBAC (8)
- 6 personas seedes via la commande app:seed-e2e, miroir cote front
  dans frontend/tests/e2e/_fixtures/personas.ts
- Page Objects (LoginPage, SidebarComponent) avec selecteurs stables
  par href + loginAs programmatique via cookie BEARER
- Targets Makefile : seed-e2e, test-e2e, test-e2e-ui, install-e2e-deps
- CLAUDE.md + README.md : workflow E2E + regle d'or "un E2E par bug
  prod uniquement" pour garder la suite maintenable dans la duree

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

frontend/package-lock.json

@@ -20,6 +20,7 @@
       },
       "devDependencies": {
         "@nuxt/eslint-config": "^1.9.0",
+        "@playwright/test": "^1.59.1",
         "@typescript-eslint/eslint-plugin": "^8.44.1",
         "@typescript-eslint/parser": "^8.44.1",
         "@vitejs/plugin-vue": "^6.0.6",
@@ -3895,6 +3896,22 @@
         "node": ">=14"
       }
     },
+    "node_modules/@playwright/test": {
+      "version": "1.59.1",
+      "resolved": "https://registry.npmjs.org/@playwright/test/-/test-1.59.1.tgz",
+      "integrity": "sha512-PG6q63nQg5c9rIi4/Z5lR5IVF7yU5MqmKaPOe0HSc0O2cX1fPi96sUQu5j7eo4gKCkB2AnNGoWt7y4/Xx3Kcqg==",
+      "dev": true,
+      "license": "Apache-2.0",
+      "dependencies": {
+        "playwright": "1.59.1"
+      },
+      "bin": {
+        "playwright": "cli.js"
+      },
+      "engines": {
+        "node": ">=18"
+      }
+    },
     "node_modules/@polka/url": {
       "version": "1.0.0-next.29",
       "resolved": "https://registry.npmjs.org/@polka/url/-/url-1.0.0-next.29.tgz",
@@ -12613,6 +12630,53 @@
         "pathe": "^2.0.3"
       }
     },
+    "node_modules/playwright": {
+      "version": "1.59.1",
+      "resolved": "https://registry.npmjs.org/playwright/-/playwright-1.59.1.tgz",
+      "integrity": "sha512-C8oWjPR3F81yljW9o5OxcWzfh6avkVwDD2VYdwIGqTkl+OGFISgypqzfu7dOe4QNLL2aqcWBmI3PMtLIK233lw==",
+      "dev": true,
+      "license": "Apache-2.0",
+      "dependencies": {
+        "playwright-core": "1.59.1"
+      },
+      "bin": {
+        "playwright": "cli.js"
+      },
+      "engines": {
+        "node": ">=18"
+      },
+      "optionalDependencies": {
+        "fsevents": "2.3.2"
+      }
+    },
+    "node_modules/playwright-core": {
+      "version": "1.59.1",
+      "resolved": "https://registry.npmjs.org/playwright-core/-/playwright-core-1.59.1.tgz",
+      "integrity": "sha512-HBV/RJg81z5BiiZ9yPzIiClYV/QMsDCKUyogwH9p3MCP6IYjUFu/MActgYAvK0oWyV9NlwM3GLBjADyWgydVyg==",
+      "dev": true,
+      "license": "Apache-2.0",
+      "bin": {
+        "playwright-core": "cli.js"
+      },
+      "engines": {
+        "node": ">=18"
+      }
+    },
+    "node_modules/playwright/node_modules/fsevents": {
+      "version": "2.3.2",
+      "resolved": "https://registry.npmjs.org/fsevents/-/fsevents-2.3.2.tgz",
+      "integrity": "sha512-xiqMQR4xAeHTuB9uWm+fFRcIOgKBMiOBP+eXiyT7jsgVCq1bkVygt00oASowB7EdtpOHaaPgKt812P9ab+DDKA==",
+      "dev": true,
+      "hasInstallScript": true,
+      "license": "MIT",
+      "optional": true,
+      "os": [
+        "darwin"
+      ],
+      "engines": {
+        "node": "^8.16.0 || ^10.6.0 || >=11.0.0"
+      }
+    },
     "node_modules/pluralize": {
       "version": "8.0.0",
       "resolved": "https://registry.npmjs.org/pluralize/-/pluralize-8.0.0.tgz",