feat: Réinitialisation de mot de passe avec tokens sécurisés

Implémentation complète du flux de réinitialisation de mot de passe (Story 1.5):

Backend:
- Aggregate PasswordResetToken avec TTL 1h, UUID v7, usage unique
- Endpoint POST /api/password/forgot avec rate limiting (3/h par email, 10/h par IP)
- Endpoint POST /api/password/reset avec validation token
- Templates email (demande + confirmation)
- Repository Redis avec TTL 2h pour distinguer expiré/invalide

Frontend:
- Page /mot-de-passe-oublie avec message générique (anti-énumération)
- Page /reset-password/[token] avec validation temps réel des critères
- Gestion erreurs: token invalide, expiré, déjà utilisé

Tests:
- 14 tests unitaires PasswordResetToken
- 7 tests unitaires RequestPasswordResetHandler
- 7 tests unitaires ResetPasswordHandler
- Tests E2E Playwright pour le flux complet

backend/composer.lock

@@ -4,7 +4,7 @@
         "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
         "This file is @generated automatically"
     ],
-    "content-hash": "07fe67e8d6e7bdfbca22ab4e7c6a65c2",
+    "content-hash": "ff0834d39a673e5aea0d0d8fde04c9b0",
     "packages": [
         {
             "name": "api-platform/core",
@@ -4189,6 +4189,88 @@
             ],
             "time": "2026-01-28T10:46:31+00:00"
         },
+        {
+            "name": "symfony/lock",
+            "version": "v8.0.5",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/symfony/lock.git",
+                "reference": "37f0408f4dee212e922dea8f8eabd693f0e10e00"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/symfony/lock/zipball/37f0408f4dee212e922dea8f8eabd693f0e10e00",
+                "reference": "37f0408f4dee212e922dea8f8eabd693f0e10e00",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=8.4",
+                "psr/log": "^1|^2|^3"
+            },
+            "conflict": {
+                "doctrine/dbal": "<4.3"
+            },
+            "require-dev": {
+                "doctrine/dbal": "^4.3",
+                "predis/predis": "^1.1|^2.0",
+                "symfony/serializer": "^6.4|^7.0"
+            },
+            "type": "library",
+            "autoload": {
+                "psr-4": {
+                    "Symfony\\Component\\Lock\\": ""
+                },
+                "exclude-from-classmap": [
+                    "/Tests/"
+                ]
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Jérémy Derussé",
+                    "email": "jeremy@derusse.com"
+                },
+                {
+                    "name": "Symfony Community",
+                    "homepage": "https://symfony.com/contributors"
+                }
+            ],
+            "description": "Creates and manages locks, a mechanism to provide exclusive access to a shared resource",
+            "homepage": "https://symfony.com",
+            "keywords": [
+                "cas",
+                "flock",
+                "locking",
+                "mutex",
+                "redlock",
+                "semaphore"
+            ],
+            "support": {
+                "source": "https://github.com/symfony/lock/tree/v8.0.5"
+            },
+            "funding": [
+                {
+                    "url": "https://symfony.com/sponsor",
+                    "type": "custom"
+                },
+                {
+                    "url": "https://github.com/fabpot",
+                    "type": "github"
+                },
+                {
+                    "url": "https://github.com/nicolas-grekas",
+                    "type": "github"
+                },
+                {
+                    "url": "https://tidelift.com/funding/github/packagist/symfony/symfony",
+                    "type": "tidelift"
+                }
+            ],
+            "time": "2026-01-27T16:18:07+00:00"
+        },
         {
             "name": "symfony/mailer",
             "version": "v8.0.4",