v0.8.0.10 — playtest fixes: clearance rulings, the log, the map, and a save file

From the first two multiplayer playtests of v0.8.0.9, each traced before fixing.

The engine:

- A train on a card BEHIND the one departing no longer triggers a clearance
  ruling or an opposite-direction bar (#26). Reproduced from the exported
  save: X15 was held over X18 behind it, and X18 then collided into the full
  Whistle Post. Games in progress holding a ruling the engine no longer asks
  for will not resume (28 of 40 recorded four-seat games); shipped as is at
  Jesse's call.
- `mainlineModified` carries the card's previous kind, so the log can say
  what a Realignment converted (#27).

The screen:

- The turn chart and the Division map name the player whose move is on
  screen while bot turns replay, not the live actor (#25).
- The owning player's name is no longer outlined by the turn arrow's stroke,
  which made it unreadable (#24).
- A Mainline card flashes on the map when a Realignment changes it (#28).
- The history is held back with the board and revealed step by step, instead
  of arriving whole while the board is still catching up (#29).
- A ruling made by holding the office reads "Superintendent Player X" (#30),
  and no line names a player twice (#31).
- A seated player can download their own game as a save file: the play
  page's Save replay button, fed by GET /api/save?token=… (#32). The StartOS
  action cannot do this — an action result is text only.

Closes #24
Closes #25
Closes #26
Closes #27
Closes #28
Closes #29
Closes #30
Closes #31
Closes #32

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_017nnuCv8UodHucFfx3LWEoX

src/engine/events.ts

@@ -87,7 +87,13 @@ export type GameEvent =
   | { type: 'deckReshuffled'; order: CardId[]; rngState: number }
   /** `variant` is the chosen orientation (Gap 11); it must be replayable, so it rides the event. */
   | { type: 'cardPlayed'; player: PlayerIndex; cardId: CardId; placement?: GridCoord; variant?: number }
-  | { type: 'mainlineModified'; player: PlayerIndex; cardId: CardId; node: number; key: string; became?: string }
+  /**
+    * `from` is the card's kind BEFORE the change, carried so the log can say what was realigned
+    * rather than only what it turned into (playtest, 2026-09-15: "it should state that the mainline
+    * card 3 curves was converted to plains"). Events are derived by replaying a save, never stored,
+    * so widening one strands nothing on disk.
+    */
+  | { type: 'mainlineModified'; player: PlayerIndex; cardId: CardId; node: number; key: string; from?: string; became?: string }
   /** §Q (Gitea#19) — a flag planted on one side of a district's Limits. */
   | { type: 'redFlagsSet'; player: PlayerIndex; cardId: CardId; seat: SeatIndex; side: Direction }
   /** §Q (Gitea#19) — the flag stopped a train and came down with it. One card, one train. */