A tally store is stamped with the buckets, not the clock

[torstei]

Drops logline_lag before it ships, and removes the reason it existed.

The stamping

Sink::write stamped now_ms. A chunk's window is now the min/max of the
bucket stamps in it (append_windowed), so both of a tally store's clocks are
the minutes its lines are about, and --from/--to selects its chunks exactly.
A backfill of last month lands in chunks stamped last month, where selection
prunes.

The rule the receive intakes already follow — ROADMAP.md:441, "both intakes
stamp chunks with the sender's EVENT time". Stamping the moment of
computation was the odd one out.

The recorded justification was stale. docs/plans/tally.md said the gap made "a
revision written an hour late findable on the first" — revisions were replaced by
displacement, so nothing arrives late any more and the gap carried no
information. Nothing read it: cursors hold the chunk seq, not a time
(format.rs:139), and duplicate buckets are combined by the field's own rule
(timbergraph.py:264), not by arrival order.

The knob

Gone entirely — the manifest key, its parse-check, the widening that consulted
it, the derivation on every provisioned store, the info line and the prose.
WIDEN_MS is the minute of widening it always was, unchanged for every store
on disk.

Set too low it selects no chunk and answers nothing, which reads exactly like a
quiet minute; set wide enough for a backfill it prunes nothing and every query
is a full scan. Its one reliable value was the one tally derived, and tally no
longer needs it. The case that remains — an arrival-stamped store whose lines
carry earlier stamps — is ROADMAP.md:16's zone-map sidecar, which answers it
exactly and cannot be set wrong.

One consequence, documented

timberfs tally | timberfs append --into X is stamped on arrival, as any pipe
is, so a logline window over that store finds nothing. That is append's
meaning, not tally's. Noted where the pipeline is shown in deployment.md and
in timberfs(1).

Tests

• what_is_written_reports_the_minutes_it_is_about pins the window the write
  path stamps with, including the !meta line's stamp.
• The VM logline-window assertion moved from the hand-rolled append pipeline
  to tally_provisioning_end_to_end, where it now runs with nothing
  declared: the source lines are dated 2026-09-06 and the run is today, so a
  store stamped at computation time would fail it.

Net −82 lines.