Add bot to play against.

internal/game/sim.go

@@ -0,0 +1,35 @@
+package game
+
+// SimulateBattle resolves a hypothetical two-player battle between the given
+// arranged decks (top of deck first) and returns the result. It runs on a
+// scratch game, so it never touches real state — callers (notably the AI
+// player) can roll out as many what-if battles as they like. Dice rolls are
+// random unless rollDie is non-nil.
+func SimulateBattle(round, prioritySeat int, deckA, deckB []Card, rollDie func() int) *BattleResult {
+	g := &Game{
+		Round:        round,
+		PrioritySeat: prioritySeat,
+		RollDie:      rollDie,
+		// Cards minted during the simulation (apples, bees) get IDs far away
+		// from real ones, purely to avoid confusion when reading results.
+		NextCardID: 1_000_000,
+		Players: []*Player{
+			{Name: "A", Seat: 0, Deck: append([]Card(nil), deckA...)},
+			{Name: "B", Seat: 1, Deck: append([]Card(nil), deckB...)},
+		},
+	}
+	g.resolveBattle()
+	return g.Battle
+}
+
+// TierContents returns the full printed contents of a tier's shop deck —
+// public information from the box. Cards carry placeholder IDs; they are
+// reference data, not live instances.
+func TierContents(tier int) []Card {
+	scratch := &Game{}
+	scratch.buildShopDecks()
+	if tier < 1 || tier > len(scratch.ShopDecks) {
+		return nil
+	}
+	return scratch.ShopDecks[tier-1]
+}