feat: v2 — view-key payment confirmation with live monitoring

- Payment monitor: enter private view key to track incoming payments
- Scans mempool + last 100 blocks via PHP proxy with 4-node failover
- Lightweight crypto: 30KB noble-curves bundle (Ed25519 + Keccak-256)
- Subaddress support (network byte 42 detection, a*D validation)
- Confirmation progress bar (0-10 confirmations)
- Underpayment detection
- Deadline badges (7/14/30 days) replacing minutes input
- QR code: standard colors (black on white) for wallet scanner compatibility
- QR hint positioned below QR code
- View key masked input, never stored or transmitted

i18n.js

@@ -14,8 +14,9 @@ var I18n = (function () {
       label_amount: 'Betrag',
       label_desc: 'Beschreibung (optional)',
       placeholder_desc: 'z.B. Rechnung #42, Freelance-Arbeit...',
-      label_timer: 'Zahlungsfrist in Minuten (optional)',
-      placeholder_timer: 'z.B. 30',
+      label_timer: 'Zahlungsfrist (optional)',
+      days: 'Tage',
+      placeholder_timer_custom: 'Tage',
       btn_generate: 'Zahlungsanforderung erstellen',
       btn_open_wallet: 'In Wallet öffnen',
       btn_copy_addr: 'Adresse kopieren',
@@ -25,8 +26,25 @@ var I18n = (function () {
       btn_new_request: 'Neue Zahlungsanforderung',
       toast_copied: 'Kopiert!',
       countdown_expired: 'Zahlungsfrist abgelaufen',
-      countdown_remaining: 'Zahlungsfrist: ',
-      rates_offline: 'Kurse nicht verfügbar — nur XMR-Betrag möglich'
+      countdown_remaining_days: 'Zahlungsfrist: {d} Tage, {h}:{m}:{s}',
+      countdown_remaining_hours: 'Zahlungsfrist: {h}:{m}:{s}',
+      rates_offline: 'Kurse nicht verfügbar — nur XMR-Betrag möglich',
+      btn_monitor: 'Zahlung überwachen',
+      label_view_key: 'Privater View-Key',
+      placeholder_view_key: '64 Hex-Zeichen...',
+      hint_view_key: 'Der View-Key verlässt nie deinen Browser',
+      btn_start_monitor: 'Überwachung starten',
+      btn_stop_monitor: 'Überwachung beenden',
+      monitor_connecting: 'Verbinde mit Node...',
+      monitor_scanning: 'Scanne Mempool...',
+      monitor_waiting: 'Warte auf Zahlung...',
+      monitor_mempool: 'Zahlung erkannt (unbestätigt)',
+      monitor_confirmed: 'Zahlung bestätigt',
+      monitor_confirmations: '{n}/10 Bestätigungen',
+      monitor_underpaid: 'Unterzahlung erkannt',
+      monitor_underpaid_detail: 'Erwartet: {expected} XMR — Erhalten: {received} XMR',
+      monitor_node_error: 'Node nicht erreichbar — versuche nächsten...',
+      monitor_loading: 'Lade Kryptografie-Modul...'
     },
     en: {
       subtitle: 'Monero payment request in seconds',
@@ -35,8 +53,9 @@ var I18n = (function () {
       label_amount: 'Amount',
       label_desc: 'Description (optional)',
       placeholder_desc: 'e.g. Invoice #42, freelance work...',
-      label_timer: 'Payment deadline in minutes (optional)',
-      placeholder_timer: 'e.g. 30',
+      label_timer: 'Payment deadline (optional)',
+      days: 'days',
+      placeholder_timer_custom: 'Days',
       btn_generate: 'Create payment request',
       btn_open_wallet: 'Open in wallet',
       btn_copy_addr: 'Copy address',
@@ -46,8 +65,25 @@ var I18n = (function () {
       btn_new_request: 'New payment request',
       toast_copied: 'Copied!',
       countdown_expired: 'Payment deadline expired',
-      countdown_remaining: 'Payment deadline: ',
-      rates_offline: 'Rates unavailable — XMR amount only'
+      countdown_remaining_days: 'Deadline: {d} days, {h}:{m}:{s}',
+      countdown_remaining_hours: 'Deadline: {h}:{m}:{s}',
+      rates_offline: 'Rates unavailable — XMR amount only',
+      btn_monitor: 'Monitor payment',
+      label_view_key: 'Private view key',
+      placeholder_view_key: '64 hex characters...',
+      hint_view_key: 'Your view key never leaves your browser',
+      btn_start_monitor: 'Start monitoring',
+      btn_stop_monitor: 'Stop monitoring',
+      monitor_connecting: 'Connecting to node...',
+      monitor_scanning: 'Scanning mempool...',
+      monitor_waiting: 'Waiting for payment...',
+      monitor_mempool: 'Payment detected (unconfirmed)',
+      monitor_confirmed: 'Payment confirmed',
+      monitor_confirmations: '{n}/10 confirmations',
+      monitor_underpaid: 'Underpayment detected',
+      monitor_underpaid_detail: 'Expected: {expected} XMR — Received: {received} XMR',
+      monitor_node_error: 'Node unreachable — trying next...',
+      monitor_loading: 'Loading crypto module...'
     }
   };