v0.3.0 — playtest fixes, two new rules, and §7 enforced

src/engine/intents.ts

@@ -136,6 +136,26 @@ export type RejectionCode =
   | 'ON_RUNNING_TRACK'
   /** A card with no east-west road would dead-end the Running Track it was laid in. */
   | 'BREAKS_RUNNING_TRACK'
+  /**
+   * A turnout may be laid on top of a straight, or of a curve on the same arc as its diverging leg
+   * — but only those, and only while the square is idle. See `checkTurnoutUpgrade`.
+   */
+  | 'NOT_UPGRADEABLE_TRACK'
+  /** You cannot swap the track out from under a standing car. */
+  | 'UPGRADE_OCCUPIED'
+  /** An Interlocking or Telegraph is built on that card; the upgrade would have to lift it. */
+  | 'UPGRADE_ENHANCED'
+  /**
+   * §7 — the operating rules printed on a train's own card. Each names the restriction it broke, so
+   * the UI can say which card is refusing rather than "illegal move".
+   */
+  | 'NO_SWITCHING'
+  | 'NOT_A_TERMINAL'
+  | 'COACH_MUST_STAY'
+  | 'FREIGHT_WORKED_HERE'
+  | 'NO_PASSENGER_WORK'
+  | 'PICKUP_NOT_ALLOWED'
+  | 'EMPTIES_ONLY'
   | 'NOT_IMPLEMENTED'
   | 'WRONG_INTENT'
   | 'NOT_A_GRADE'