Update policy management and documentation

- Bumped the version of the `lol.mleku.dev` dependency from v1.0.3 to v1.0.4.
- Removed redundant checks for disabled policy in event handling.
- Introduced a `default_policy` field in the policy configuration, allowing for more flexible event handling based on default behaviors.
- Enhanced documentation to clarify the default policy logic and its implications on event processing.
- Updated tests to validate the new default policy behavior and ensure correct fallback mechanisms are in place.

docs/example-policy.json

@@ -1,4 +1,5 @@
 {
+  "default_policy": "allow",
   "kind": {
     "whitelist": [0, 1, 3, 4, 5, 6, 7, 40, 41, 42, 43, 44, 9735],
     "blacklist": []