feat(validations): merchant (bar/lavazh) ticket validations end-to-end

In-park merchants discharge customers' parking: a merchant user scans the
ticket on their device (/validate; validation:create + program↔user binding)
and applies their program — comp / first-N-minutes free / amount-off (capped,
typed at scan) / percent. All money stays at the booth: the quote folds live
validations in a canonical order (timeCredit → percent → fixed → comp, net
floors at 0, Σ lines ≡ gross − net), the payment records gross/discount and
CONSUMES the validation ids (an overstay's fresh period never re-applies
them), the receipt prints the gross → lines → net story, and the Z/X-report
carries discountTotalMinor leakage. Every apply/void is a signed, attributed
ledger event (refId = append-only void); program config is /setup/site master
data (Bar/Lavazh checkboxes + right-column panel, tabs when both) whose saves
sign config_change. Migration 0024 + reset-db drift-guard entries; 8 route
integration tests + priceSession fold suite.

See wiki/concepts/validation-discounts.md for the full design record.

Claude-Session: https://claude.ai/code/session_01YYkpEsLmoQPaize5ec3oUm

apps/web/src/ui/event-detail.tsx

@@ -25,6 +25,7 @@ export const EVENT_STYLE: Record<string, { labelKey: string; color: string }> =
   cash_out: { labelKey: "booth.evtCashOut", color: "text-term-amber" },
   cash_review: { labelKey: "booth.evtCashReview", color: "text-term-cyan" },
   config_change: { labelKey: "booth.evtConfigChange", color: "text-term-amber" },
+  validation: { labelKey: "booth.evtValidation", color: "text-term-green" },
   anomaly: { labelKey: "booth.evtAnomaly", color: "text-term-red" },
 };