feat: configurable fee rates via VITE_CASH_IN_FEE and VITE_CASH_OUT_FEE

Accepts percentage (5.55) or decimal (0.0555) — auto-detected by
whether the value is >= 1. Defaults to 3.33% cash-in, 7.77% cash-out.

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

apps/machine/src/stores/atm.ts

@@ -260,6 +260,8 @@ export const useAtmStore = defineStore('atm', () => {
   const allowMockFallback = ref(true) // default true for browser dev
   const initError = ref<string | null>(null) // fatal error → maintenance screen
   const fiatCode = ref('USD')
+  const cashInFeeRate = ref(0.0333)
+  const cashOutFeeRate = ref(0.0777)
   const machineModel = ref('atm')
   const useLiveServices = ref(false)
   const connectionStatus = ref<'disconnected' | 'connecting' | 'connected' | 'error'>(
@@ -359,7 +361,11 @@ export const useAtmStore = defineStore('atm', () => {
   // Actions
   function initialize(services: ATMServices = mockServices) {
     atmServicesRef = services
-    const machine = createATMMachine(services, { currency: fiatCode.value })
+    const machine = createATMMachine(services, {
+      currency: fiatCode.value,
+      cashInFeeRate: cashInFeeRate.value,
+      cashOutFeeRate: cashOutFeeRate.value,
+    })
     actor.value = createActor(machine)
 
     // Track previous state to detect transitions into 'complete'
@@ -925,6 +931,9 @@ export const useAtmStore = defineStore('atm', () => {
     machineModel.value = model
     const runtimeFiatCode = runtimeConfig.fiatCode || 'USD'
     fiatCode.value = runtimeFiatCode
+    if (runtimeConfig.cashInFeeRate !== undefined) cashInFeeRate.value = runtimeConfig.cashInFeeRate
+    if (runtimeConfig.cashOutFeeRate !== undefined)
+      cashOutFeeRate.value = runtimeConfig.cashOutFeeRate
 
     // Build device config from runtime values
     const { getDeviceConfig, toHalConfig, MACHINE_PRESETS } = await import('@/config')

apps/machine/src/types/electron.d.ts

@@ -16,6 +16,8 @@ export interface RuntimeConfig {
   allowMockFallback: boolean
   operatorPubkeys: string
   maintenanceMode: boolean
+  cashInFeeRate: number
+  cashOutFeeRate: number
 }
 
 export interface AtmSecrets {