feat(email): Implement email service with SMTP configuration, template rendering, and example usage

- Added EmailService class for sending emails using nodemailer with support for templates.
- Implemented TemplateRenderer for rendering email templates using Pug.
- Created various email templates: welcome, password reset, and notification.
- Added example usage functions for sending different types of emails.
- Included validation for email templates and SMTP configuration.
- Established a structured approach for handling email attachments and recipients.
- Introduced TypeScript types and Zod schemas for type safety and validation.

Author: JasonKrik

package-lock.json

@@ -7,6 +7,11 @@ A modular and extensible backend API for the DeployStack CI/CD platform, built w
 - **High-performance**: Built on Fastify for optimal speed and efficiency
 - **Type-safe**: Written in TypeScript for better development experience
 - **Modular**: Well-organized code structure for maintainability
+- **Email System**: Integrated email service with Pug templates and SMTP support
+- **Global Settings**: Centralized configuration management with encryption
+- **Database Integration**: SQLite/PostgreSQL support with Drizzle ORM
+- **Plugin System**: Extensible architecture for custom functionality
+- **Authentication**: Lucia-based authentication with role management
 - **Logging**: Comprehensive request logging with request IDs and timing
 - **Developer-friendly**: Pretty logging in development, production-ready in production
 
@@ -59,22 +64,68 @@ npm run lint
 ```bash
 services/backend/
 ├── src/
-│   ├── config/         # Configuration files
-│   │   └── logger.ts   # Logger configuration
-│   ├── hooks/          # Fastify hooks
-│   │   └── request-logger.ts  # Request logging hooks
-│   ├── plugins/        # Fastify plugins
-│   │   └── index.ts    # Plugin registration
-│   ├── routes/         # API routes
-│   │   └── index.ts    # Route definitions
+│   ├── api/            # API route handlers
+│   ├── db/             # Database configuration and schema
+│   │   ├── config.ts   # Database connection setup
+│   │   ├── index.ts    # Database exports
+│   │   ├── migrations.ts # Migration management
+│   │   └── schema.ts   # Database schema definitions
+│   ├── email/          # Email system (NEW)
+│   │   ├── templates/  # Pug email templates
+│   │   │   ├── layouts/    # Base layout components
+│   │   │   │   ├── base.pug    # Main email layout
+│   │   │   │   ├── header.pug  # Email header
+│   │   │   │   └── footer.pug  # Email footer
+│   │   │   ├── welcome.pug     # Welcome email template
+│   │   │   ├── password-reset.pug # Password reset template
+│   │   │   └── notification.pug   # General notification template
+│   │   ├── emailService.ts     # Main email service
+│   │   ├── templateRenderer.ts # Pug template renderer
+│   │   ├── types.ts           # Email type definitions
+│   │   ├── example.ts         # Usage examples
+│   │   └── index.ts           # Email module exports
+│   ├── fastify/        # Fastify configuration
+│   │   ├── config/     # Fastify setup
+│   │   ├── hooks/      # Request/response hooks
+│   │   └── plugins/    # Fastify plugins
+│   ├── global-settings/ # Global configuration system
+│   │   ├── github-oauth.ts # GitHub OAuth settings
+│   │   ├── smtp.ts     # SMTP email settings
+│   │   ├── types.ts    # Global settings types
+│   │   └── index.ts    # Settings initialization
+│   ├── hooks/          # Authentication hooks
+│   ├── lib/            # External library integrations
+│   │   └── lucia.ts    # Lucia authentication setup
+│   ├── middleware/     # Request middleware
+│   ├── plugin-system/  # Plugin architecture
+│   ├── plugins/        # Available plugins
+│   ├── routes/         # API route definitions
+│   │   ├── auth/       # Authentication routes
+│   │   ├── db/         # Database management routes
+│   │   ├── globalSettings/ # Settings management routes
+│   │   ├── roles/      # Role management routes
+│   │   └── users/      # User management routes
+│   ├── services/       # Business logic services
+│   │   ├── globalSettingsService.ts # Settings service
+│   │   ├── roleService.ts           # Role management
+│   │   ├── teamService.ts           # Team management
+│   │   └── userService.ts           # User management
 │   ├── types/          # TypeScript type definitions
-│   │   └── fastify.ts  # Fastify type extensions
 │   ├── utils/          # Utility functions
-│   │   └── banner.ts   # Startup banner
+│   │   ├── banner.ts   # Startup banner
+│   │   └── encryption.ts # Encryption utilities
 │   ├── server.ts       # Server configuration
 │   └── index.ts        # Application entry point
+├── drizzle/            # Database migrations
+├── persistent_data/    # Persistent application data
+├── tests/              # Test files
 ├── .env                # Environment variables (not in version control)
-├── .eslintrc           # ESLint configuration
+├── DB.md               # Database documentation
+├── GLOBAL_SETTINGS.md  # Global settings documentation
+├── Mail.md             # Email system documentation (NEW)
+├── PLUGINS.md          # Plugin system documentation
+├── ROLES.md            # Role management documentation
+├── SECURITY.md         # Security documentation
 ├── package.json        # Package dependencies and scripts
 └── tsconfig.json       # TypeScript configuration
 ```
@@ -95,6 +146,43 @@ The `services/backend/persistent_data/` directory is designated for storing all
 
 This ensures that persistent data is managed in a predictable way and is not scattered across the project.
 
+## 📧 Email System
+
+DeployStack includes a comprehensive email system with Pug templates and SMTP integration:
+
+### Quick Start
+
+```typescript
+import { EmailService } from './src/email';
+
+// Send a welcome email
+await EmailService.sendWelcomeEmail({
+  to: '[email protected]',
+  userName: 'John Doe',
+  userEmail: '[email protected]',
+  loginUrl: 'https://app.deploystack.com/login'
+});
+
+// Send a notification
+await EmailService.sendNotificationEmail({
+  to: '[email protected]',
+  title: 'Deployment Complete',
+  message: 'Your app has been deployed successfully.'
+});
+```
+
+### Configuration
+
+1. Configure SMTP settings in the global settings interface
+2. Required settings: `smtp.host`, `smtp.port`, `smtp.username`, `smtp.password`
+3. Optional settings: `smtp.secure`, `smtp.from_name`, `smtp.from_email`
+
+### Documentation
+
+- **[Mail.md](./Mail.md)**: Complete email system documentation
+- **Templates**: Located in `src/email/templates/`
+- **Examples**: See `src/email/example.ts` for usage examples
+
 ## 🌍 Environment Variables
 
 Create a `.env` file in the `services/backend` directory with the following variables:
@@ -103,7 +191,7 @@ Create a `.env` file in the `services/backend` directory with the following vari
 NODE_ENV=development
 PORT=3000
 LOG_LEVEL=debug
-FOO=bar  # Example environment variable used in the demo route
+DEPLOYSTACK_ENCRYPTION_SECRET=your-32-character-secret-key-here  # Required for global settings encryption
 ```
 
 ## 🤝 Contributing

services/backend/Mail.md

@@ -23,8 +23,10 @@
     "fastify": "^5.3.3",
     "fastify-favicon": "^5.0.0",
     "lucia": "^3.2.2",
+    "nodemailer": "^6.9.8",
     "pino": "^9.7.0",
     "pino-pretty": "^13.0.0",
+    "pug": "^3.0.2",
     "zod": "^3.25.42"
   },
   "devDependencies": {
@@ -35,6 +37,8 @@
     "@types/better-sqlite3": "^7.6.13",
     "@types/fs-extra": "^11.0.4",
     "@types/jest": "^29.5.14",
+    "@types/nodemailer": "^6.4.14",
+    "@types/pug": "^2.0.10",
     "@types/supertest": "^6.0.3",
     "@typescript-eslint/eslint-plugin": "^8.33.0",
     "@typescript-eslint/parser": "^8.33.0",