fix: container installs, Tor, kiosk, GRUB, LUKS display, error messages

Critical:
- fix: container installs fail with "statfs: no such file or directory"
  Root cause: NoNewPrivileges=yes in systemd blocks sudo inside backend.
  Fix: use std::fs::create_dir_all + podman unshare chown (no sudo needed)
- fix: Tor services.json never written — \$ARCHY_TOR_DIR escaping bug
- fix: kiosk white screen — increase health wait to 60s, add --disable-gpu

Improvements:
- feat: LUKS encryption badge in Server disk stats (backend detects dm-crypt)
- fix: GRUB theme text scaling on 4:3 monitors — explicit fonts, wider menu
- fix: suppress default Debian MOTD (custom profile.d welcome is enough)
- fix: install error messages now show "Failed to pull/start" instead of
  generic "Operation failed" (middleware.rs allowlist expanded)
- fix: container-tests CI — source cargo env before running tests
- docs: interactive container architecture diagram (HTML)

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

image-recipe/branding/grub-theme/theme.txt

@@ -1,6 +1,5 @@
 # Archipelago GRUB Theme
 # Dark background with Bitcoin orange accents
-# Font references removed — GRUB uses whatever fonts are loaded in grub.cfg
 
 title-text: ""
 desktop-color: "#0a0a0a"
@@ -8,41 +7,46 @@ desktop-image: "background.png"
 desktop-image-scale-method: "stretch"
 
 + boot_menu {
-    left = 15%
-    top = 40%
-    width = 70%
-    height = 35%
+    left = 10%
+    top = 35%
+    width = 80%
+    height = 40%
+    item_font = "DejaVu Sans Bold 16"
     item_color = "#aaaaaa"
+    selected_item_font = "DejaVu Sans Bold 16"
     selected_item_color = "#f7931a"
-    item_height = 40
-    item_spacing = 10
-    item_padding = 20
+    item_height = 36
+    item_spacing = 8
+    item_padding = 16
     scrollbar = false
 }
 
 + label {
-    left = 25%
-    top = 20%
-    width = 50%
+    left = 10%
+    top = 18%
+    width = 80%
+    font = "DejaVu Sans Mono Bold 24"
     text = "a r c h i p e l a g o"
     color = "#f7931a"
     align = "center"
 }
 
 + label {
-    left = 25%
-    top = 28%
-    width = 50%
+    left = 10%
+    top = 26%
+    width = 80%
+    font = "DejaVu Sans Bold 14"
     text = "bitcoin node os"
     color = "#888888"
     align = "center"
 }
 
 + label {
-    left = 25%
+    left = 10%
     top = 90%
-    width = 50%
-    text = "use arrow keys to select, enter to boot"
+    width = 80%
+    font = "DejaVu Sans Bold 12"
+    text = "press tab to edit  |  use arrow keys to select  |  enter to boot"
     color = "#555555"
     align = "center"
 }