Add Linting Infrastructure and CI/CD Pipeline (and Prettier reformatting)

.github/workflows/ci.yml

@@ -0,0 +1,99 @@
+name: Test and Build
+
+on:
+  pull_request:
+    branches: [main]
+  push:
+    branches: [main]
+
+jobs:
+  lint:
+    name: Lint
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: '22.12.0'
+
+      # Frontend Linting
+      - name: Install frontend dependencies
+        working-directory: packages/demo-app-frontend
+        run: npm ci
+
+      - name: Run ESLint (Frontend)
+        working-directory: packages/demo-app-frontend
+        run: npm run lint
+
+      - name: Check Prettier formatting (Frontend)
+        working-directory: packages/demo-app-frontend
+        run: npx prettier --check .
+
+      # Solidity Linting
+      - name: Install contract dependencies
+        working-directory: packages/trust-anchor-did-ethr
+        run: npm ci
+
+      - name: Run Solhint (Contracts)
+        working-directory: packages/trust-anchor-did-ethr
+        run: npx solhint 'contracts/**/*.sol'
+
+  test:
+    name: Test
+    needs: lint
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: '22.12.0'
+          cache: 'npm'
+          cache-dependency-path: packages/trust-anchor-did-ethr/package-lock.json
+
+      - name: Install dependencies
+        working-directory: packages/trust-anchor-did-ethr
+        run: npm ci
+
+      - name: Run Hardhat tests
+        working-directory: packages/trust-anchor-did-ethr
+        run: npx hardhat test
+
+  build:
+    name: Build
+    needs: test
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: '22.12.0'
+
+      # Compile Contracts
+      - name: Install contract dependencies
+        working-directory: packages/trust-anchor-did-ethr
+        run: npm ci
+
+      - name: Compile smart contracts
+        working-directory: packages/trust-anchor-did-ethr
+        run: npx hardhat compile
+
+      # Build Frontend
+      - name: Install frontend dependencies
+        working-directory: packages/demo-app-frontend
+        run: npm ci
+
+      - name: Build frontend
+        working-directory: packages/demo-app-frontend
+        run: npm run build

.husky/pre-commit

@@ -0,0 +1 @@
+cd packages/demo-app-frontend && npx lint-staged

BUILD.md

@@ -7,6 +7,7 @@
 - [Installation](#installation)
 - [Running the Project](#running-the-project)
 - [Testing](#testing)
+- [Development Workflow](#development-workflow)
 - [TypeScript Configuration](#typescript-configuration)
 - [Platform-Specific Notes](#platform-specific-notes)
 - [Deployment](#deployment)
@@ -66,6 +67,14 @@ This project uses the following key dependencies:
 
 ## Installation
 
+### Install Root Dependencies
+
+First, install root dependencies (required for Husky pre-commit hooks):
+
+```bash
+npm install
+```
+
 ### Install Dependencies for Each Package
 
 #### 1. Smart Contracts (trust-anchor-did-ethr)
@@ -187,6 +196,45 @@ cd packages/demo-app-frontend
 npm run lint
 ```
 
+## Development Workflow
+
+### Pre-commit Hooks
+
+This project uses [Husky](https://typicode.github.io/husky/) and [lint-staged](https://github.com/okonet/lint-staged) to automatically lint your code before commits:
+
+**What happens when you commit:**
+1. You stage files: `git add src/components/MyComponent.tsx`
+2. You commit: `git commit -m "fix: update component"`
+3. Pre-commit hook runs automatically:
+   - ESLint checks code quality and fixes issues
+   - Prettier formats code (indentation, spacing, etc.)
+   - Both tools auto-fix and re-stage files
+   - Unfixable errors block the commit
+4. If successful, commit proceeds with clean, formatted code
+
+**Manual formatting:**
+```bash
+npm run format  # Format all files with Prettier
+npm run lint    # Check code quality with ESLint
+```
+
+**Configuration:**
+- Hook script: `.husky/pre-commit`
+- Prettier rules: `packages/demo-app-frontend/.prettierrc`
+- ESLint rules: `packages/demo-app-frontend/eslint.config.js`
+- Staged file rules: `packages/demo-app-frontend/package.json` → `lint-staged` section
+
+### Continuous Integration (GitHub Actions)
+
+Pull requests and pushes to `main` trigger automated checks (`.github/workflows/ci.yml`):
+
+**CI Jobs:**
+1. **Frontend Linting**: Runs ESLint on entire frontend codebase
+2. **Frontend Formatting**: Checks Prettier formatting compliance
+3. **Contract Validation**: Compiles smart contracts and runs full test suite
+
+**All checks must pass before merging.** The CI uses Node.js 22.12.0 to match local development.
+
 ## TypeScript Configuration
 
 ### Smart Contracts (trust-anchor-did-ethr)