ui: move chain delete button to right, use ✕ glyph

- C-APDU chain rows: delete button moved after the hex field (matches
  Expanded Script layout)
- Use ✕ uniformly across delete icons (was × in chain rows)

SW cache v49.

frontend/sw.js

@@ -1,4 +1,4 @@
-const CACHE = 'otaman-v48';
+const CACHE = 'otaman-v49';
 const URLS = [
   'index.html',
   'help.html',