Fix pg deprecation warning: set search_path via connection options

Replace pool.on('connect') query with connection-level options parameter.
Avoids calling client.query() during handshake, which pg will remove in v9.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

api/server.js

@@ -16,7 +16,8 @@ const pool = new Pool({
     port: process.env.DB_PORT,
     database: process.env.DB_NAME,
     user: process.env.DB_USER,
-    password: process.env.DB_PASSWORD
+    password: process.env.DB_PASSWORD,
+    options: '-c search_path=dataflow,public'
 });
 
 // Middleware
@@ -31,11 +32,6 @@ app.use('/api', auth);
 const path = require('path');
 app.use(express.static(path.join(__dirname, '../public')));
 
-// Set search path for all queries
-pool.on('connect', (client) => {
-    client.query('SET search_path TO dataflow, public');
-});
-
 // Test database connection
 pool.query('SELECT NOW()', (err, res) => {
     if (err) {