Add backend API for personal finance management application

- Introduced a comprehensive backend API using TypeScript, Fastify, and PostgreSQL.
- Added essential files including architecture documentation, environment configuration, and Docker setup.
- Implemented RESTful routes for managing assets, liabilities, clients, invoices, and cashflow.
- Established a robust database schema with Prisma for data management.
- Integrated middleware for authentication and error handling.
- Created service and repository layers to adhere to SOLID principles and clean architecture.
- Included example environment variables for development, staging, and production setups.

backend-api/src/server.ts

@@ -0,0 +1,98 @@
+import Fastify from 'fastify';
+import cors from '@fastify/cors';
+import jwt from '@fastify/jwt';
+import swagger from '@fastify/swagger';
+import swaggerUi from '@fastify/swagger-ui';
+import {env} from './config/env';
+import {errorHandler} from './middleware/errorHandler';
+import {authRoutes} from './routes/auth';
+import {assetRoutes} from './routes/assets';
+import {liabilityRoutes} from './routes/liability.routes';
+import {clientRoutes} from './routes/client.routes';
+import {invoiceRoutes} from './routes/invoice.routes';
+import {netWorthRoutes} from './routes/networth.routes';
+import {debtRoutes} from './routes/debt.routes';
+import {cashflowRoutes} from './routes/cashflow.routes';
+import {dashboardRoutes} from './routes/dashboard.routes';
+
+/**
+ * Create and configure Fastify server
+ * Implements Single Responsibility: Server configuration
+ */
+export async function buildServer() {
+  const fastify = Fastify({
+    logger: {
+      level: env.NODE_ENV === 'development' ? 'info' : 'error',
+      transport: env.NODE_ENV === 'development' ? {target: 'pino-pretty'} : undefined,
+    },
+  });
+
+  // Register plugins
+  await fastify.register(cors, {
+    origin: env.CORS_ORIGIN,
+    credentials: true,
+  });
+
+  await fastify.register(jwt, {
+    secret: env.JWT_SECRET,
+    sign: {
+      expiresIn: env.JWT_EXPIRES_IN,
+    },
+  });
+
+  // Register Swagger for API documentation
+  await fastify.register(swagger, {
+    openapi: {
+      info: {
+        title: 'Personal Finances API',
+        description: 'API for managing personal finances including assets, liabilities, invoices, and more',
+        version: '1.0.0',
+      },
+      servers: [
+        {
+          url: `http://localhost:${env.PORT}`,
+          description: 'Development server',
+        },
+      ],
+      components: {
+        securitySchemes: {
+          bearerAuth: {
+            type: 'http',
+            scheme: 'bearer',
+            bearerFormat: 'JWT',
+          },
+        },
+      },
+    },
+  });
+
+  await fastify.register(swaggerUi, {
+    routePrefix: '/docs',
+    uiConfig: {
+      docExpansion: 'list',
+      deepLinking: false,
+    },
+  });
+
+  // Register error handler
+  fastify.setErrorHandler(errorHandler);
+
+  // Health check
+  fastify.get('/health', async () => ({
+    status: 'ok',
+    timestamp: new Date().toISOString(),
+  }));
+
+  // Register routes
+  await fastify.register(authRoutes, {prefix: '/api/auth'});
+  await fastify.register(assetRoutes, {prefix: '/api/assets'});
+  await fastify.register(liabilityRoutes, {prefix: '/api/liabilities'});
+  await fastify.register(clientRoutes, {prefix: '/api/clients'});
+  await fastify.register(invoiceRoutes, {prefix: '/api/invoices'});
+  await fastify.register(netWorthRoutes, {prefix: '/api/net-worth'});
+  await fastify.register(debtRoutes, {prefix: '/api/debts'});
+  await fastify.register(cashflowRoutes, {prefix: '/api/cashflow'});
+  await fastify.register(dashboardRoutes, {prefix: '/api/dashboard'});
+
+  return fastify;
+}