Expose OST MessageStore to JS runtime

[puffyCid]

What new feature do you think would be cool to add to artemis?
Artemis already can parse the OST MessageStore metadata. However, it currently does not output the metadata natively.
To access the MessageStore metadata, we should add bindings to it via the JS runtime so it can be accessed via TypeScript scripts

Describe the solution you'd like
Expose parsing the MessageStore data to JS runtime