feat(backend): Prisma schema, Express routes, audit middleware, error handling

backend/src/routes/auditLogs.js

@@ -0,0 +1,54 @@
+const router = require('express').Router();
+const { query } = require('express-validator');
+const prisma = require('../lib/prisma');
+const { validateRequest } = require('../middleware/errorHandler');
+
+// GET /api/audit-logs?tableName=&recordId=&limit=&offset= — query logs
+router.get(
+  '/',
+  [
+    query('tableName').optional().isString(),
+    query('recordId').optional().isUUID().withMessage('recordId must be a valid UUID'),
+    query('limit').optional().isInt({ min: 1, max: 200 }).withMessage('limit must be 1–200').toInt(),
+    query('offset').optional().isInt({ min: 0 }).withMessage('offset must be ≥0').toInt(),
+  ],
+  validateRequest,
+  async (req, res, next) => {
+    try {
+      const { tableName, recordId } = req.query;
+      const limit = req.query.limit || 50;
+      const offset = req.query.offset || 0;
+
+      const where = {};
+      if (tableName) where.table_name = tableName;
+      if (recordId) where.record_id = recordId;
+
+      const [logs, total] = await Promise.all([
+        prisma.auditLog.findMany({
+          where,
+          orderBy: { timestamp: 'desc' },
+          take: limit,
+          skip: offset,
+        }),
+        prisma.auditLog.count({ where }),
+      ]);
+
+      res.json({ logs, total, limit, offset });
+    } catch (err) {
+      next(err);
+    }
+  }
+);
+
+// GET /api/audit-logs/:id — single log entry
+router.get('/:id', async (req, res, next) => {
+  try {
+    const log = await prisma.auditLog.findUnique({ where: { id: req.params.id } });
+    if (!log) return res.status(404).json({ error: 'Audit log not found' });
+    res.json(log);
+  } catch (err) {
+    next(err);
+  }
+});
+
+module.exports = router;