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/discover/AppGrid.vue

@@ -57,7 +57,7 @@
                 :class="getAppTier(app.id) === 'core' ? 'tier-badge-core' : 'tier-badge-recommended'"
               >{{ getAppTier(app.id) }}</span>
             </div>
-            <p class="text-sm text-white/50">{{ app.version ? `v${app.version}` : 'latest' }}</p>
+            <p class="text-sm text-white/50">{{ app.version ? $ver(app.version) : 'latest' }}</p>
             <p v-if="app.author" class="text-xs text-white/40 mt-0.5">{{ app.author }}</p>
           </div>
         </div>

neode-ui/src/views/discover/FeaturedApps.vue

@@ -37,7 +37,7 @@
               >{{ getAppTier(app.id) }}</span>
               <span v-if="isInstalled(app.id)" class="discover-installed-badge">installed</span>
             </div>
-            <p class="text-white/50 text-sm mb-3">{{ app.author }} &middot; v{{ app.version }}</p>
+            <p class="text-white/50 text-sm mb-3">{{ app.author }} &middot; {{ $ver(app.version) }}</p>
             <p class="text-white/80 text-sm leading-relaxed">{{ app.featuredDescription }}</p>
           </div>
         </div>