Add forceFullHTTPReads filesystem config flag.

[jheer]

This PR adds a new filesystem configuration option: forceFullHTTPReads. If enabled, this flag suppresses the use of HTTP range requests for DuckDB-WASM running in the browser.

The flag is set via the database open method:

const worker = new Worker(config.mainWorker);
const db = new AsyncDuckDB(new ConsoleLogger(), worker);
await db.instantiate(config.mainModule, config.pthreadWorker);
await db.open({
  filesystem: {
    forceFullHTTPReads: true
  }
});

The flag passes in through WASM (C code), and back to a worker thread (TypeScript code) where the actual file loads are performed.

Why add this flag?

• Firefox has bad interactions with range requests and compression on some servers (including GitHub Pages), causing file loading in DuckDB-WASM to crash rather than gracefully fallback to full reads. Setting this flag sidesteps the error and enables successful file loading.
• When one knows ahead of time that the full data is needed, full file reads can be more efficient by making a single HTTP call rather than multiple.
• Full file reads result in fewer operations when connecting to object storage like R2 and S3, potentially reducing bills.

[carlopi]

Thanks!!

[Fil]

Thanks! Do we have a recommended pattern in the case where we don't know if we need to enable this flag? A try/catch?