fix(backend): Convert legacy queries and add translate wrapper

backend/transform.js

@@ -0,0 +1,46 @@
+#!/usr/bin/env node
+/**
+ * transform.js
+ * Converte server.js de sintaxe MySQL/adapter para PostgreSQL nativo (pg).
+ * Uso: node transform.js > server_new.js
+ */
+import { readFileSync, writeFileSync } from 'fs';
+
+let code = readFileSync('./server.js', 'utf8');
+
+// 1. Remove the dead initTables function (MySQL DDL, never called)
+code = code.replace(/\/\/ Initialization: Create tables if not exist[\s\S]*?^\/\/ initTables\(\); removed from here\s*/m, '');
+
+// 2. Fix all simple ? placeholders in pool.query calls
+// Strategy: for each pool.query or client.query call, replace ? sequentially with $1, $2...
+function fixPlaceholders(sql) {
+    let i = 0;
+    return sql.replace(/\?/g, () => `$${++i}`);
+}
+
+// 3. Replace INSERT INTO table SET ? with helper call marker
+// 4. Replace UPDATE table SET ? WHERE id = ? with helper call marker
+// These need manual per-call replacement, done below
+
+// Fix simple queries with ? -> $n (for strings not containing SET ?)
+code = code.replace(/pool\.query\('([^']*?)'\s*,\s*\[([^\]]+)\]\)/g, (match, sql, params) => {
+    if (sql.includes('SET ?') || sql.includes('SET?')) return match; // skip complex
+    const fixed = fixPlaceholders(sql);
+    return `pool.query('${fixed}', [${params}])`;
+});
+
+code = code.replace(/pool\.query\(`([\s\S]*?)`\s*,\s*\[([^\]]+)\]\)/g, (match, sql, params) => {
+    if (sql.includes('SET ?') || sql.includes('ON DUPLICATE')) return match;
+    const fixed = fixPlaceholders(sql);
+    return `pool.query(\`${fixed}\`, [${params}])`;
+});
+
+// Fix client.query inside withTransaction
+code = code.replace(/client\.query\('([^']*?)'\s*,\s*\[([^\]]+)\]\)/g, (match, sql, params) => {
+    if (sql.includes('SET ?')) return match;
+    const fixed = fixPlaceholders(sql);
+    return `client.query('${fixed}', [${params}])`;
+});
+
+writeFileSync('./server_transformed.js', code, 'utf8');
+console.log('Done. Check server_transformed.js');