feat(ui): dual-ecash wallet settings, buy-peer-files, seed backup, assorted fixes

- Tabbed Wallet Settings modal (Cashu + Fedimint) and dual-balance wallet card
- Buy a peer's paid file (ecash / node Lightning / on-chain / external QR)
- Recovery-phrase reveal + backup section; onboarding seed retry resilience
- NetBird HTTPS launch, remote-control two-finger scroll + external-open
- Shared BackButton, single-v version label, mesh Bitcoin header toggles

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

neode-ui/src/views/apps/appsConfig.ts

@@ -170,6 +170,8 @@ export const TAB_LAUNCH_APPS = new Set([
   'btcpay-server', 'grafana', 'photoprism', 'homeassistant',
   'vaultwarden', 'nextcloud', 'uptime-kuma', 'portainer', 'gitea',
   'cryptpad', 'nginx-proxy-manager', 'tailscale',
+  // netbird's dashboard needs HTTPS (secure context) so it opens in a new tab
+  'netbird',
 ])
 
 export function opensInTab(id: string): boolean {