Refactor js package build process for removing the need for `await init()` call

Currently when we import the package to a project, we need to use the following syntax to initialize wasm.

```ts
import init, { SQLiteWasmDatabase. } from "@rainlanguage/sqlite-web"

await init();
const db = SQLiteWasmDatabase.new('test.db');
```

This is not the best DX so we need to be able to just import the db constructor and not use init.