fix:

- AES GCM protocol mismatch
- better, granular error handling
- UUID now uses crypto.randomUUID()
- added native mlock addon to improve security
- ZeroBuffer uses explicit_bzero now
- fixed imports

feat:
-  added unit tests

native/index.js

@@ -0,0 +1,13 @@
+/**
+ * Native mlock addon entry point.
+ * Loaded via node-gyp-build which selects the correct pre-built binary for
+ * the current platform/Node.js version, or falls back to building from source.
+ *
+ * Returns null if the native addon is not available, allowing the JS layer
+ * to fall back to pure-JS zeroing.
+ */
+try {
+    module.exports = require('node-gyp-build')(__dirname);
+} catch (_e) {
+    module.exports = null;
+}