Review follow-ups on b9b2e593f, all documentation precision.
The redundancy note on `isCompactCheckpoint` leaned on a reading its call
site does not state: `index.ts` reaches it for surface-eligible non-append
events, which is the same set as replacements only because the marker is
mandatory. Say that instead.
The Agent Note now owns three facts it was leaving to a future reader.
`rebuildTranscript` materializes a component per append-origin event and
runs on mount, color-scheme change, and every reasoning toggle — work
compaction used to bound for exactly the long sessions it serves, so the
cost now tracks session length rather than the surface. `Consequences`
names `surface-replayed-compaction` as the durable evidence for the
live/replay equivalence claim, so the two fixtures that must move together
are findable from the Note rather than the PR thread. `Deferred` records
that a page can now carry a checkpoint whose `surfaceOp.start` fell out of
the window: pagination no longer cuts on the checkpoint's provenance
group, `FoldAdapter` pads with a non-surface sentinel, and `nodes()`
degrades to `degradedSeqs()` — which is already close to the transcript
projection A2 should build deliberately.
Also corrects the definite-assignment comment in the snapshot scenario:
the assertion rests on the awaited setup invoking `beforeMount`, not on
that call being synchronous.
Hypatia May
b7bb4842df