Amplify announces itself

Room 9BBV's "impossible" 14-point powerthrust was an archmage playing
correctly: 2 + 5, AMPLIFIED. The engine's math was honest and its
narration was not — neither the log line nor the attack modal
mentioned the amplify, so a legal kill read as a bug. The spellCast
event now carries its amplify count, the chronicle says "casts
Powerthrust with a 5, AMPLIFIED, at Kestrel", and the modal's power
line shows "powered by a 5 — AMPLIFIED ×2" while there is still time
to respect it.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

packages/engine/src/game.ts

@@ -483,7 +483,8 @@ export type GameEvent =
   | { type: "moved"; player: PlayerId; from: Cell; to: Cell; direction: Side; via: "step" | "warp" | "passWall" }
   | { type: "numberPlayedForMovement"; player: PlayerId; card: CardInstance; value: number; newAllowance: number }
   | { type: "punched"; attacker: PlayerId; target: PlayerId; at: Cell }
-  | { type: "spellCast"; caster: PlayerId; card: CardInstance; cardId: string; numberCards: CardInstance[]; numberValue: number | null; from: Cell; target: PlayerId | null; targetCell: Cell | null }
+  | { type: "spellCast"; caster: PlayerId; card: CardInstance; cardId: string; numberCards: CardInstance[]; numberValue: number | null; from: Cell; target: PlayerId | null; targetCell: Cell | null;
+      /** AMPLIFY cards attached (each doubles). */ amplifies?: number }
   | { type: "counteractionPlayed"; player: PlayerId; card: CardInstance; cardId: string; against: string }
   | { type: "counterNullified"; player: PlayerId; card: CardInstance; by: CardInstance }
   | { type: "attackAbsorbedIntoHand"; player: PlayerId; attackCard: CardInstance }
@@ -4496,6 +4497,7 @@ function doCast(prev: GameState, cmd: Extract<Command, { type: "cast" }>): Comma
       cardId: inHand.cardId,
       numberCards: mods.numbers,
       numberValue: mods.magnitude.numberValue,
+      amplifies: mods.amplifies.length,
       from: caster.position,
       target: target.id,
       targetCell: target.position,