Ton premier pipeline

# Depuis la racine de ton projet
mkdir -p .github/workflows
touch .github/workflows/ci.yml

# .github/workflows/ci.yml
name: CI

on:
  push:
    branches: [main]
  pull_request:
    branches: [main]

jobs:
  ci:
    name: Lint, Type Check & Build
    runs-on: ubuntu-latest

    steps:
      - name: Checkout du code
        uses: actions/checkout@v4

      - name: Setup Node.js
        uses: actions/setup-node@v4
        with:
          node-version: 20
          cache: 'npm'
          cache-dependency-path: frontend/package-lock.json

      - name: Installer les dependances
        working-directory: frontend
        run: npm ci

      - name: Lint
        working-directory: frontend
        run: npm run lint

      - name: Type Check
        working-directory: frontend
        run: npx tsc --noEmit

      - name: Build
        working-directory: frontend
        run: npm run build

git add .github/workflows/ci.yml
git commit -m "ci: ajouter pipeline CI (lint, type-check, build)"
git push origin main

# Erreur typique : "Process completed with exit code 1"
# Le step a échoué. Clique sur le step rouge pour voir les logs.

# Erreurs courantes :
# 1. npm ci failed -> package-lock.json absent ou obsolète
#    Fix : npm install puis commit le package-lock.json

# 2. Lint errors -> ESLint a trouvé des erreurs
#    Fix : npm run lint en local, corrige, re-push

# 3. Type errors -> TypeScript a trouvé des erreurs
#    Fix : npx tsc --noEmit en local, corrige les types

# 4. Build failed -> erreur de compilation Next.js
#    Fix : npm run build en local pour reproduire l'erreur

# Dans ton README.md, ajoute ce badge :
# ![CI](https://github.com/TON-USER/TON-REPO/actions/workflows/ci.yml/badge.svg)

# Le badge affiche automatiquement :
# - Vert : CI passing
# - Rouge : CI failing
# - Gris : pas encore exécuté

# Version optimisée avec jobs parallèles :
jobs:
  lint:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: actions/setup-node@v4
        with: { node-version: 20, cache: 'npm', cache-dependency-path: frontend/package-lock.json }
      - run: npm ci
        working-directory: frontend
      - run: npm run lint
        working-directory: frontend

  typecheck:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: actions/setup-node@v4
        with: { node-version: 20, cache: 'npm', cache-dependency-path: frontend/package-lock.json }
      - run: npm ci
        working-directory: frontend
      - run: npx tsc --noEmit
        working-directory: frontend

  build:
    needs: [lint, typecheck]  # Build seulement si lint + typecheck passent
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: actions/setup-node@v4
        with: { node-version: 20, cache: 'npm', cache-dependency-path: frontend/package-lock.json }
      - run: npm ci
        working-directory: frontend
      - run: npm run build
        working-directory: frontend