feat(lnd): capture aezeed at wallet init + encrypted backup + reveal UI

- aezeed words are now captured at BOTH wallet-init paths and stored
  encrypted (Argon2 + ChaCha20-Poly1305, per-node wallet secret) at
  identity/lnd_aezeed.enc; ack marker cleared when a wallet is recreated
- lnd.init-wallet-from-seed was posting seed_entropy to /v1/initwallet,
  which is a GenSeed field — the wallet was never actually derived from
  the master seed; now GenSeed(entropy) → InitWallet(words)
- new RPCs: lnd.seed-backup-status / lnd.seed-reveal (password + 2FA
  gated, same as seed.reveal via shared verify_reveal_auth) /
  lnd.seed-backup-ack
- LND app detail page: Lightning-seed card with first-launch backup
  prompt, tap-to-reveal modal, 'I've backed it up' acknowledgment

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

neode-ui/src/views/AppDetails.vue

@@ -19,6 +19,8 @@
         @channels="router.push('/dashboard/apps/lnd/channels')"
       />
 
+      <LndSeedBackup v-if="packageKey === 'lnd' && pkg.installed" />
+
       <div class="grid grid-cols-1 lg:grid-cols-3 gap-6">
         <AppContentSection
           :pkg="pkg"
@@ -86,6 +88,7 @@ import BackButton from '@/components/BackButton.vue'
 import AppHeroSection from './appDetails/AppHeroSection.vue'
 import AppContentSection from './appDetails/AppContentSection.vue'
 import AppSidebar from './appDetails/AppSidebar.vue'
+import LndSeedBackup from './appDetails/LndSeedBackup.vue'
 import AppsUninstallModal from './apps/AppsUninstallModal.vue'
 import { resolveAppUrl } from './appSession/appSessionConfig'
 import { resolveAppCredentials } from './apps/appCredentials'