v0.5.4 — the map says whose railroad is whose

Six things found playing the StartOS build, all of them the game telling
you what it already knew.

The lobby's Start button did not look disabled when it was. The reported
symptom was "it says it's waiting for a player but Start is enabled" — it
wasn't: the note and the disabled assignment are two lines apart in the
same block. The page had only `header button:disabled` and `#actions
button:disabled`, and #lb-start is in neither, so a disabled button kept
its normal face AND still lit up under the cursor from the generic
button:hover. It advertised a click it would refuse. The rule is generic
now.

The game code was rendered as "— code TRESTLE-5109" in dim text beside a
heading, reading like a reference number rather than the thing you have to
send somebody. It is a labelled block at 22px with a Copy button, and a
clipboard refusal says the code can be selected instead of failing
silently. The blurb under it was also WRONG — it claimed the chairs were
"in the order everyone joined", which stopped being true in v0.4.1 when the
§4.4 D12 started deciding. It now says what actually happens.

Every Office on the Division map was labelled with its tier, which every
other player's Office also has, so four districts read identically and
"where does Bob sit" had no answer on the one map showing where trains are.
The owner's name takes the headline and the tier moves beside the A/D
count. Amber marks whose move it is — the same "happening here" the action
panel uses — and "(you)" is spelled out on the reader's own district,
because colour alone cannot say which of four railroads is yours. Turn
colour wins over the you-colour when both apply: whose turn it is changes
every few seconds, which railroad is yours never does.

Under the map, the chain in words with the roll behind it: "West to East:
Alice (1) → Bot 2 (5) → Bot 1 (11)". state.openingRolls has been kept for
exactly this since v0.4.1 and nothing had displayed it. It also answers
"is the host always at the eastern end" outright — no. Alice there is the
host, rolled lowest, and sits at the western end.

Supporting: Frame gained viewer and viewerSeat. Every private field on it
was already scoped to one player, but nothing said which player, so a page
could draw a railroad without being able to say whose it was — harmless in
solitaire, the first question at four seats. Frame also gained
openingRolls. Bots are Bot 1 / Bot 2 rather than all Bot, since two of them
are two different railroads. The standalone replay gets all of it: players,
actor and viewer are not delta'd keys in compress, so they ride whole on
every frame and replay.ts passes the same roster.

Verified: 673 tests pass (668 + 5). The new ones were mutation-checked —
removing the (you) suffix, never applying the turn mark, and reinstating
the pre-v0.4.1 identity seating each fail the suite. The seating test
deliberately asserts across six seeds that the eastern end is NOT always
player 0, which is the claim it exists to defend.

src/sim/view.ts

@@ -370,6 +370,23 @@ export type Frame = {
    * player order once §4.4's D12 decided who sits where.
    */
   players: { index: number; seat: number; name: string; revenue: number; hand: number }[];
+  /**
+   * WHO THIS FRAME WAS BUILT FOR.
+   *
+   * Every private thing on a Frame is already scoped to one player — the hand, the Office Area,
+   * `revenue`, `option`, `movesLeft` — but nothing said which player that was, so a page rendering
+   * it could show a railroad without being able to say whose it is. Harmless in solitaire, where
+   * there is only one; the first thing you want to know at a four-player table.
+   */
+  viewer: number;
+  /** The viewer's position in the west-to-east chain, which is not their player index (§4.4). */
+  viewerSeat: number;
+  /**
+   * §4.4's opening D12 per player, and the roll that chose the Superintendent — kept so a client
+   * can show the chain being formed rather than only its result (`lobby-and-sessions.md` §4).
+   * Indexed by player, like `s.players`, not by seat.
+   */
+  openingRolls: { division: number[]; superintendent: number[] };
   /** How many cards the VIEWER holds. Other players' counts are in `players`. */
   handCount: number;
   /**
@@ -1241,6 +1258,12 @@ export function snapshot(
       revenue: p.revenue,
       hand: (s.decks.hands.get(p.index) ?? []).length,
     })),
+    viewer,
+    viewerSeat,
+    openingRolls: {
+      division: [...s.openingRolls.division],
+      superintendent: [...s.openingRolls.superintendent],
+    },
     handCount: (s.decks.hands.get(viewer) ?? []).length,
     overHandLimit:
       (s.decks.hands.get(viewer) ?? []).length > (s.decks.redFlags.get(viewer) ? HAND_LIMIT + 1 : HAND_LIMIT),