v0.8.0.2 — the speed control that was only ever a URL parameter, and a Day-end

contradiction

Two things found by playing v0.8.0.1, neither in the mechanism itself.

?pace= never worked. index.html's doors are play.html?lobby and
play.html?solitaire, so arriving through the splash replaces the query string and
the play page only ever saw ?lobby — a whole game was played at 1x while believing
it was at 7x. v0.8.0 shipped that parameter as the only way to change speed and the
game's own front door destroyed it. There is a control on the play screen now,
beside zoom, persisted per viewer; the doors carry pace through as well, so the URL
lever is honest for handing two playtesters different speeds. PACE_LEVELS moved to
sim/pacing.ts with DWELL and MAX_PACE — the tuning surface in one file, and
testable. The committed default is unchanged: what it should be is a question for a
game played at a speed that took effect.

And the Day-end dialog said "0 today, 2 in all". advance.ts increments the Day and
then zeroes collisionsToday, and noteDayEnd() fires when the Day goes up — so the
dialog reporting the Day that just finished was drawn from the very frame in which
that Day's count was reset. Reproduced on four of five seeds before changing
anything. The count is captured at the rollover now; it is not derivable on the
client, because in multiplayer the push announcing the new Day is the same push
that carries the reset. And "today" was the wrong word regardless: it names the Day
instead — "Collisions: 2 on Day 1, 2 in all".

Unrelated to v0.8.0 — that one has been wrong since the dialog was built for
Gitea#10, and needed somebody to play a Day with a collision in it and then read
the summary.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01X6cF1iYvJ1kNmzYBzu4QX6

src/engine/state.ts

@@ -1119,6 +1119,20 @@ export type GameState = {
   movedThisPhase: Set<TrayId>;
   /** §3.4 — resets at the start of each Day; checked against `config.maxCollisionsPerDay`. */
   collisionsToday: number;
+  /**
+   * What `collisionsToday` held for the Day that just ENDED — captured at the rollover, immediately
+   * before the reset.
+   *
+   * The Day-end dialog exists to report the Day that finished, and it is drawn from the frame AFTER
+   * the rollover, because that is the frame whose `day` went up. So it read `collisionsToday` as 0 no
+   * matter what had happened: Jesse, 2026-09-09, at the end of a Day 1 with two collisions in it —
+   * "it shows a total of two collisions, but zero today ... that does seem to be a contradiction".
+   *
+   * NOT DERIVABLE ON THE CLIENT. A Day turns over inside the phases that run themselves, so in
+   * multiplayer the push that reports the new Day is the same push that reports the reset — a client
+   * may never see the ended Day's final count to remember it.
+   */
+  collisionsPrevDay: number;
   /** §3.4 — never reset; checked against `config.maxCollisionsTotal`. */
   collisionsTotal: number;
   /**