Use OPFS to store / cache local data

[derekperkins]

Now that duckdb-wasm has merged support for OPFS, we have the ability to use significant disk space if we want, allowing us to do more queries locally without having to keep everything in memory.

• Add OPFS (Origin Private File System) Support duckdb/duckdb-wasm#1856

This is referenced in #385 about query caching policies, but can be used for more than that

[jheer]

Yes, we're very interested in this as well. One first step will be to add support to pass the necesary options to the WASM connector. However, I believe you can start using it right away if you create your own DuckDB-WASM instance and pass it into the wasmConnector method.