feat(machine): record failed dispenses and per-cassette tracking

Failed dispenses (sats debited, cash not dispensed) were invisible —
transactions only recorded on 'complete'. Now records on 'dispenseError'
with status ('dispense_error'|'partial'|'complete'), error message, and
per-cassette detail.

Also fixes a bug in both HAL services where dispense results were mapped
by amounts-array index instead of cassette position, causing swapped
denomination counts when cassette order differs from request order.

Schema v3→v4: adds status/error columns to transactions, new
cassette_bills table for per-cassette provisioned/dispensed/rejected.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

packages/state-machine/src/index.ts

@@ -51,6 +51,7 @@ export {
   type PaymentStatus,
   type PaymentMethod,
   type DispenseCashResult,
+  type CassetteBillResult,
   initialContext,
 } from './types.js'
 

packages/state-machine/src/types.ts

@@ -5,14 +5,32 @@
 /** Payment status */
 export type PaymentStatus = 'pending' | 'paid' | 'failed' | null
 
+/** Per-cassette dispense result (position-aware) */
+export interface CassetteBillResult {
+  /** Cassette name, e.g. "cassette1", "cassette2" */
+  name: string
+  /** 0-indexed physical position */
+  position: number
+  /** Bill denomination in this cassette */
+  denomination: number
+  /** Bills requested from this cassette */
+  provisioned: number
+  /** Bills actually dispensed */
+  dispensed: number
+  /** Bills rejected/jammed */
+  rejected: number
+}
+
 /** Result of a dispense operation (always resolves, never throws) */
 export interface DispenseCashResult {
-  /** Per-cassette results (what was actually dispensed) */
+  /** Per-denomination results (what was actually dispensed) */
   bills: { denomination: number; dispensed: number; rejected: number }[]
   /** Whether the full requested amount was dispensed */
   dispensed: boolean
   /** Error message if dispense failed or was partial */
   error?: string
+  /** Per-cassette detail (position-aware, produced by HAL) */
+  cassettes?: CassetteBillResult[]
 }
 
 /** Payment methods supported */