Implement SimpleNote Web API - full REST API with Express

- Express server with CORS, JSON middleware
- Auth middleware (Bearer token)
- Document CRUD with markdown storage
- Library CRUD with nested support
- Tag indexing and search
- Error handler middleware
- Config from env vars
- Init script for data structure

src/index.js

@@ -4,33 +4,42 @@
  */
 
 import express from 'express';
-import { fileURLToPath } from 'url';
-import { dirname, join } from 'path';
-
-const __filename = fileURLToPath(import.meta.url);
-const __dirname = dirname(__filename);
+import cors from 'cors';
+import config from './config/index.js';
+import { createApiRouter } from './routes/index.js';
+import { errorHandler } from './middleware/errorHandler.js';
+import { initTagIndexer } from './indexers/tagIndexer.js';
+import { ensureDir } from './utils/fsHelper.js';
 
 const app = express();
-const PORT = process.env.PORT || 3000;
 
 // Middleware
-app.use(express.json());
+app.use(cors({ origin: config.corsOrigin }));
+app.use(express.json({ limit: '10mb' }));
 app.use(express.urlencoded({ extended: true }));
 
-// Health check
+// Health check (unprotected)
 app.get('/health', (req, res) => {
-  res.json({ status: 'ok', timestamp: new Date().toISOString() });
+  res.json({ status: 'ok', timestamp: new Date().toISOString(), version: '1.0.0' });
 });
 
-// TODO: Routes
-// - /api/documents
-// - /api/libraries
-// - /api/tags
-// - /api/auth
+// Ensure data directory exists
+ensureDir(config.dataRoot);
+
+// Initialize tag indexer
+console.log(`[SimpleNote] Data root: ${config.dataRoot}`);
+initTagIndexer(config.dataRoot);
+
+// Mount API routes
+app.use(config.apiPrefix, createApiRouter(config.apiPrefix));
+
+// Error handler
+app.use(errorHandler);
 
 // Start server
-app.listen(PORT, () => {
-  console.log(`SimpleNote Web running on port ${PORT}`);
+app.listen(config.port, config.host, () => {
+  console.log(`[SimpleNote] Web API running on http://${config.host}:${config.port}`);
+  console.log(`[SimpleNote] API prefix: ${config.apiPrefix}`);
 });
 
 export default app;