Long expeditions D5-a: per-tier supply pack caps

Today's global SupplyPackStandardMax=3 / SupplyPackDeluxeMax=1 were
a 2-day shape; with D1's longer room budgets and D2-b's event-anchored
night burns, a T4/T5 player can't legally buy enough supplies for the
intended duration. supplyPackCaps(tier) now returns (std,dlx) per
tier — T1/T2: (2,1); T3: (3,1) unchanged; T4: (5,1); T5: (7,2) —
sized to clear DailyBurn(raw) × intendedDays × 1.3 even with the
harsh×3 multiplier layered on. Validate takes a tier; both call sites
(!expedition start, !resume) pass the resolved zone's tier. Holiday
+1 standard pack still bypasses the cap on purpose. DailyBurn /
phase5BDailyBurnRatePct unchanged; that's a D7 lever once the sim
can measure event-anchored rollovers.

internal/plugin/dnd_expedition_extract.go

@@ -312,7 +312,8 @@ func (p *AdventurePlugin) handleResumeCmd(ctx MessageContext, args string) error
 	if err != nil {
 		return p.SendDM(ctx.Sender, "Couldn't parse supply packs: "+err.Error())
 	}
-	if err := purchase.Validate(); err != nil {
+	resumeZone, _ := getZone(exp.ZoneID)
+	if err := purchase.Validate(resumeZone.Tier); err != nil {
 		return p.SendDM(ctx.Sender, "Invalid pack selection: "+err.Error())
 	}
 	cost := float64(purchase.Cost())