feat(machine): Bolt Card (NFC) tap-to-receive on cash-in

Tap-to-receive for the buy flow, the receive counterpart to #83's
cash-out tap-to-pay. A Bolt Card only emits an lnurlw withdraw voucher
(wrong direction to deposit into it), so the tap is used as an
authenticated identity (external_id + SUN p/c) to resolve the card
wallet's lnurlp/Lightning Address; the ATM then pays an invoice for the
payout over its existing nostr transport.

- electron/lnurl-pay.ts: resolveCardInvoice() — resolve card -> pay
  target -> LUD-16/LUD-06 -> BOLT11. scanUrlToResolver() is the single
  HTTPS-today / nostr-tomorrow transport seam. 13 tests.
- IPC lnurl:pay-card (main-process HTTPS to dodge renderer CORS) +
  preload/electron.d.ts surface.
- stores/atm.ts: handleBoltCardReceive() settles via the existing
  payInvoice -> PAYMENT_RECEIVED path; the one NFC listener now routes
  the same tap by flow (cash-out pulls, cash-in receives).
- CashInView.vue: NFC status + dev tap input.
- docs/boltcard-receive-resolver.md: spec for the custom LNbits
  /boltcards/api/v1/pay/<id> resolver endpoint (omni-private side).

Card issuance is unchanged — same NDEF/keys/external_id; receive is a
server-side reading of the same tap.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

apps/machine/electron/preload.ts

@@ -134,6 +134,13 @@ contextBridge.exposeInMainWorld('electronAPI', {
     amountMsat?: number
   }): Promise<{ ok: boolean; reason?: string }> => ipcRenderer.invoke('lnurl:withdraw', args),
 
+  // Bolt Card cash-in: resolve a tapped card + amount to a BOLT11 to pay.
+  resolveCardInvoice: (args: {
+    lnurlw: string
+    amountMsat: number
+  }): Promise<{ ok: boolean; bolt11?: string; reason?: string }> =>
+    ipcRenderer.invoke('lnurl:pay-card', args),
+
   applyOperatorCassettesConfig: (
     payload: {
       positions: Record<string, { denomination: number; count: number }>
@@ -272,6 +279,10 @@ declare global {
         bolt11: string
         amountMsat?: number
       }) => Promise<{ ok: boolean; reason?: string }>
+      resolveCardInvoice: (args: {
+        lnurlw: string
+        amountMsat: number
+      }) => Promise<{ ok: boolean; bolt11?: string; reason?: string }>
       applyOperatorCassettesConfig: (
         payload: { positions: Record<string, { denomination: number; count: number }> },
         eventCreatedAt: number