Chord's shared watch: listeners take a tagged call, { kind: "value", value, ops, retired } or
{ kind: "failed", error }; a recoverable failure keeps the watch open and the next value arrives as
[["r", value]]; WatchEnd is tagged by kind, and an aborted context ends a watch "aborted".
Durable: observers take the watch's shapes (advance(call, ctx), end(end)); onReport(report) with
report.kind and report.error, session_failed is storage_failed; subscribeCommits is observeCommits;
SessionEnd and ReportFrom are tagged by kind; FileChange is tagged and file watchers stop with
stop(ctx); CompactionFailure and CompactionStatus name their trigger (pi.live version 2 with a
migrate); the task_outdated report uses the scheduler's reasons; TaskInspection's ready is pending;
DocumentCommitChange is tagged. Stored formats are unchanged.
ConversationView.entries is a window over the fork-aware history with before;
conversation.watch(ctx, { from, min, max }) and observeConversation take the
window. ConversationTranscript merges windows into a client's transcript with
gaps, loadEarlier, fillGap and resume. pi.live.runFailure says why a run ended
without an answer. watchEvents and its event types are removed; the changelog
has the migration guide.
closes#11327
