Non-async store creation for ReferenceStore

[keller-mark]

In order to use ReferenceStore, store creation becomes async. This can have a big effect on the surrounding code, as the consumer and upstream call chain therefore must become async.

zarrita.js/packages/storage/src/ref.ts

Line 102 in ee79e0a

static async fromUrl(

Could store creation for ReferenceStore be more lazy, analogous to the ZipStore?

zarrita.js/packages/storage/src/zip.ts

Line 82 in ee79e0a

static fromUrl(

ZipStore does not await (this.info) until it is needed during get

zarrita.js/packages/storage/src/zip.ts

Line 73 in ee79e0a

let entry = (await this.info).entries[strip_prefix(key)];