feat: build on wasm

[Frando]

Description

Make iroh-docs work in WebAssembly in the browser, memstore only.

Depends on n0-computer/iroh-blobs#187
Depends on n0-computer/n0-future#17
Depends on n0-computer/n0-future#16

• Has the usual changes to use n0-future for time and tasks.
• redb works in-memory in the browser. No persistent store for now. In native environments, we spawn a separate thread for the storage actor with a single-threaded tokio runtime. In wasm, we instead simply run this on the main thread. With the inmemory store this is fine, IMO.
• This PR includes a refactor that was needed anyway: A couple of methods on Replica are now async because we previously used send_blocking on a async_channel::Sender (uuh) and async_channel::Sender::send_blocking is not available on wasm.

Breaking Changes

Made a couple of methods on Replica async because we previously used send_blocking on a async_channel::Sender (uuh) and async_channel::Sender::send_blocking is not available on wasm. This is a much needed refactor anyways.

(needs more details)

Notes & open questions

Change checklist

• Self-review.
• Documentation updates following the style guide, if relevant.
• Tests if relevant.
• All breaking changes documented.

[github-actions]

Documentation for this PR has been generated and is available at: https://n0-computer.github.io/iroh-docs/pr/75/docs/iroh_docs/

Last updated: 2025-11-03T15:53:02Z