Submissions with request-ID deduplication and handles, the pi.live run
control and presentation document, the built-in pi.generation task
(system prompt preparation, streamed durable partials, retries, deferred
polling, abort), typed entry tokens, stream options and retry policy,
TaskRuntime reads, Tx.settleSubmission, registry conversation setups,
Storage.scanSubmissions, Harness.inspect, and byTaskId attribution.
Waiting calls enable scheduling. The scratch tour is split into
test/examples.