v0.1.0 — undo, the crew's reach on the board, workers on the card, and four engine bugs

Fifteen items from two playtest sessions. Three that read as drawing faults were engine
bugs: cars could be added to a train that was not being made up (50 offers in 8 games),
the make-up panel merged two trains and could couple a car to the wrong one, and an
Office upgrade silently deleted what a Modifier had added. A fourth was a sentinel
inside a coordinate's own value range — a Mainline placement travelling as row -1, which
is an ordinary district row.

Trains are now drawn the way they stand: west on the left, nose toward the way the engine
faces, on both the district card and the Division chip. Undo steps back through the game
by replaying the save without its last intent. The switching walk keeps its rejections, so
the board can say why a square is not offered. Laborers and Porters are on the card, and
the rule that a district only grows outwards is finally written down.

Versions start here: third digit for fixes, second for a feature set, 1.0 for a release.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01GgtkX8JnvKa8y2tuJ8aQf4

TODO.md

@@ -207,6 +207,15 @@ target is settled and freight carries its intended share.
       (32%), the facility object stored a second time inside its own cell (24%) and the rest of the
       static identity (26%). All three are interned now — 3415 KB → 1877 KB, and a round-trip test
       runs the page's own unpacking function.
+- [ ] **Undo is unlimited step-back, and that is a decision to revisit.** The save is the seed plus
+      the intents, so `undo()` replays without the last one and can walk all the way to the deal. The
+      RNG advances with the replay, so the same play re-rolls the same 1D12 — you cannot undo your
+      way to a better die. But you CAN see a train's departure Stage and then spend the turn
+      differently, which is an ordinary solitaire take-back and also a real information leak. Options
+      if it starts to feel like cheating: make the Stage boundary a commit point, or cap the depth at
+      the current Stage. Deliberately left open until it has been played with. Multiplayer gets
+      nothing until there is a proposal/agreement flow — undo there is a table decision, not a
+      button.
 - [ ] **The 5 MB replay size limit is arbitrary.** Invented, not a browser constraint. It has earned
       its place — it caught a 5.2 MB payload that turned out to be the whole grid re-serialised every
       frame — but the number itself deserves a reason.
@@ -214,8 +223,6 @@ target is settled and freight carries its intended share.
       close up.
 - [ ] **Wide boards scroll.** A 40-card district and a 13-section Division both need horizontal
       scrolling. Legible, not compact.
-- [ ] **No way to start a fresh game from inside the page.** `?seed=` gives a reproducible deal and
-      "new game" only appears once a game has ended, so abandoning a bad opening means editing the URL.
 - [ ] **Save/restore is not version-aware.** A save from an older ruleset stops replaying rather than
       failing loudly, which is the safe direction but says little about what changed. **This has now
       bitten once**: both published replays were dead — one got 42 intents into 360, the other 4 of