Audit logging feature files

backend/helpers/auditLog.js

@@ -0,0 +1,21 @@
+// Audit Log Helper
+// Fire-and-forget insert - never blocks the response
+
+function logAudit(db, { userId, username, action, entityType, entityId, details, ipAddress }) {
+    const detailsStr = details && typeof details === 'object'
+        ? JSON.stringify(details)
+        : details || null;
+
+    db.run(
+        `INSERT INTO audit_logs (user_id, username, action, entity_type, entity_id, details, ip_address)
+         VALUES (?, ?, ?, ?, ?, ?, ?)`,
+        [userId || null, username || 'unknown', action, entityType, entityId || null, detailsStr, ipAddress || null],
+        (err) => {
+            if (err) {
+                console.error('Audit log error:', err.message);
+            }
+        }
+    );
+}
+
+module.exports = logAudit;