Watcher Live client stays responsive when a worker stalls

Watcher Live's client now runs two request workers by default, so it can keep handling new requests even if one worker stalls, and it no longer blocks other requests while looking up local sessions during permission checks.

What's new?

• The Watcher Live client uses two request workers by default, keeping new requests responsive if one worker stalls; this increases the client's baseline memory usage.
• Local session lookups performed during permission checks no longer block the client's other requests.