ci : add pull_request quality gate workflow

Workflow Gitea declenche sur chaque PR ciblant develop, avec deux jobs
paralleles :
- backend : composer install, php-cs-fixer dry-run, bootstrap DB test
  (service postgres:16-alpine), phpunit
- frontend : npm ci, eslint, vitest, nuxt build

Ajoute aussi la cible make php-cs-fixer-check (dry-run) pour avoir la
meme commande en local et en CI.

E2E volontairement hors scope (regle d'or testing.md : tests E2E
uniquement pour bug critique passe en prod).

.gitea/workflows/pull-request.yml

@@ -0,0 +1,118 @@
+name: Pull Request — Quality gate
+
+# Lance les tests + lint + build sur chaque PR ciblant develop.
+# Deux jobs en parallele (backend / frontend) pour reduire le temps de feedback.
+# E2E volontairement hors scope (cf. regle d'or testing.md).
+
+on:
+  pull_request:
+    branches:
+      - develop
+
+# Annule les runs obsoletes quand on repush sur la meme PR.
+concurrency:
+  group: pr-${{ gitea.event.pull_request.number }}
+  cancel-in-progress: true
+
+jobs:
+  backend:
+    name: Backend (PHP CS + PHPUnit)
+    runs-on: ubuntu-latest
+
+    services:
+      postgres:
+        image: postgres:16-alpine
+        env:
+          # Doivent matcher la DATABASE_URL ci-dessous (et le default
+          # de phpunit.dist.xml). Le suffixe `_test` est applique
+          # automatiquement par Doctrine en APP_ENV=test.
+          POSTGRES_USER: app
+          POSTGRES_PASSWORD: '!ChangeMe!'
+          POSTGRES_DB: app
+        ports:
+          - 5432:5432
+        options: >-
+          --health-cmd "pg_isready -U app"
+          --health-interval 5s
+          --health-timeout 5s
+          --health-retries 10
+
+    env:
+      APP_ENV: test
+      APP_SECRET: ci-secret-not-used
+      APP_DEBUG: 0
+      DEFAULT_URI: http://localhost/
+      DATABASE_URL: postgresql://app:!ChangeMe!@127.0.0.1:5432/app?serverVersion=16&charset=utf8
+      JWT_SECRET_KEY: '%kernel.project_dir%/config/jwt/private.pem'
+      JWT_PUBLIC_KEY: '%kernel.project_dir%/config/jwt/public.pem'
+      JWT_PASSPHRASE: change_me_in_env_local
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Setup PHP 8.4
+        uses: shivammathur/setup-php@v2
+        with:
+          php-version: '8.4'
+          extensions: pdo, pdo_pgsql, intl, opcache, zip, mbstring, sodium
+          coverage: none
+          tools: composer:v2
+
+      - name: Cache Composer
+        uses: actions/cache@v4
+        with:
+          path: ~/.composer/cache
+          key: composer-${{ hashFiles('composer.lock') }}
+          restore-keys: |
+            composer-
+
+      - name: Install PHP dependencies
+        run: composer install --no-interaction --no-progress --prefer-dist
+
+      - name: Generate JWT keypair
+        run: php bin/console lexik:jwt:generate-keypair --skip-if-exists --no-interaction
+
+      - name: PHP CS Fixer (dry-run)
+        run: vendor/bin/php-cs-fixer fix --config=.php-cs-fixer.dist.php --allow-risky=yes --dry-run --diff
+
+      - name: Bootstrap test database
+        run: |
+          php bin/console doctrine:database:create --env=test --if-not-exists --no-interaction
+          php bin/console doctrine:migrations:migrate --env=test --no-interaction
+          php bin/console doctrine:schema:update --env=test --force --no-interaction
+          php bin/console doctrine:fixtures:load --env=test --no-interaction
+          php bin/console app:sync-permissions --env=test --no-interaction
+
+      - name: Run PHPUnit
+        run: php -d memory_limit=512M vendor/bin/phpunit
+
+  frontend:
+    name: Frontend (lint + Vitest + build)
+    runs-on: ubuntu-latest
+    defaults:
+      run:
+        working-directory: frontend
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Setup Node 22
+        uses: actions/setup-node@v4
+        with:
+          node-version: '22'
+          cache: npm
+          cache-dependency-path: frontend/package-lock.json
+
+      - name: Install Node dependencies
+        run: npm ci
+
+      - name: ESLint
+        run: npm run lint
+
+      - name: Unit tests (Vitest)
+        run: npm run test
+
+      - name: Build production (nuxt build)
+        run: npm run build:dist