Keep deck storted sensibly during shop phase.

internal/game/game.go

@@ -410,12 +410,36 @@ func (g *Game) startShopRound() {
 		for _, c := range slices.Clone(p.Deck) {
 			g.applyShopTrigger(p, c, TriggerShopStart)
 		}
+		g.sortShopDeck(p)
 	}
 	// The priority-token holder shops first.
 	g.Turn = g.PrioritySeat
 	g.logf(-1, "🛒", "Round %d — shop opens (%s goes first).", g.Round, g.Players[g.PrioritySeat].Name)
 }
 
+// sortShopDeck stably reorders a player's deck for the shop's default
+// display: pets first, then perk foods, then everything else (apples and
+// other loose foods). Deck order carries no battle meaning during the shop —
+// the battle uses the permutation each player submits in the arrange phase
+// (see SubmitOrder) — so this is purely a cosmetic default that keeps freshly
+// bought pets grouped at the front. The stable sort preserves buy order
+// within each category.
+func (g *Game) sortShopDeck(p *Player) {
+	rank := func(c Card) int {
+		switch {
+		case c.IsPet():
+			return 0
+		case c.IsFood() && c.Perk:
+			return 1
+		default:
+			return 2
+		}
+	}
+	slices.SortStableFunc(p.Deck, func(a, b Card) int {
+		return rank(a) - rank(b)
+	})
+}
+
 // drawFromTier pops the top card of the given tier's deck (1-based tier).
 // Returns a zero Card if the deck is empty.
 func (g *Game) drawFromTier(tier int) Card {
@@ -1011,6 +1035,10 @@ func (g *Game) Pass(playerID string) error {
 // the shop, and it requires being at the pet limit, so no cleanup step is
 // needed here.
 func (g *Game) advanceShopTurn() {
+	// The player who just acted may have changed their deck (bought, sold,
+	// traded, or triggered an apple-granting effect); keep it in the shop's
+	// default order for them before handing off.
+	g.sortShopDeck(g.Players[g.Turn])
 	for i := 1; i <= len(g.Players); i++ {
 		seat := (g.Turn + i) % len(g.Players)
 		if !g.Players[seat].Ready {