fix: container security hardening, onboarding viewport scaling, boot screen cleanup

Container security:
- Add --cap-drop ALL + --security-opt no-new-privileges:true to 12 containers
  missing hardening in first-boot-containers.sh (mempool-db, electrumx,
  mempool-api, mempool-web, electrs-ui, btcpay-db, nbxplorer, nostr-rs-relay,
  strfry, tailscale, bitcoin-ui, lnd-ui)
- Mirror same hardening in deploy-to-target.sh for consistency
- Add --read-only + tmpfs to nostr-rs-relay
- Fix filebrowser deploy to include security flags
- Remove duplicate UI image definitions in image-versions.sh
- Separate Jellyfin capabilities (needs FOWNER, exec tmpfs for CoreCLR JIT)
- Harden archy-net creation with existence check and error handling

UI fixes:
- Fix onboarding viewport scaling: all 7 screens now use h-full + max-h-full
  pattern so containers never overflow viewport regardless of padding
- Remove path-option-card wrappers from seed verify inputs, left-justify labels
- Remove batteries/barbarian icons from boot screen (keep bitcoin, cloud, github, save)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

neode-ui/src/views/OnboardingIdentity.vue

@@ -1,6 +1,6 @@
 <template>
-  <div class="min-h-full flex items-center justify-center p-3 sm:p-4 md:p-6">
-    <div class="max-w-[800px] w-full relative z-10 path-glass-container onb-scroll-container">
+  <div class="h-full flex items-center justify-center p-3 sm:p-4 md:p-6">
+    <div class="max-w-[800px] w-full max-h-full relative z-10 path-glass-container onb-scroll-container flex flex-col">
       <!-- Header -->
       <div class="text-center flex-shrink-0 px-3 sm:px-4 pt-4 sm:pt-6">
         <h1 class="text-xl sm:text-2xl md:text-[26px] font-semibold text-white/96 mb-2 sm:mb-4 drop-shadow-[0_2px_6px_rgba(0,0,0,0.4)]">
@@ -11,7 +11,8 @@
         </p>
       </div>
 
-      <!-- Content -->
+      <!-- Scrollable Content -->
+      <div class="flex-1 overflow-y-auto overflow-x-hidden min-h-0">
       <div class="flex flex-col items-center gap-4 sm:gap-6 mb-4 sm:mb-6 px-3 sm:px-4">
         <div class="w-full max-w-[600px] space-y-4 sm:space-y-6">
           <!-- Name Input -->
@@ -59,9 +60,10 @@
         <p class="text-orange-400/80 text-sm">Server is still starting up. Your identity will be saved once it's ready.</p>
       </div>
       <p v-else-if="errorMessage" class="text-red-400 text-sm text-center mb-4">{{ errorMessage }}</p>
+      </div>
 
       <!-- Action Buttons -->
-      <div class="flex justify-center max-w-[600px] mx-auto flex-shrink-0 px-3 sm:px-4 pb-4 sm:pb-6">
+      <div class="flex justify-center max-w-[600px] mx-auto flex-shrink-0 px-3 sm:px-4 pb-4 sm:pb-6 pt-3">
         <button
           @click="createIdentity"
           :disabled="isCreating"