feat(send): animated hash-bag on the "Transaction Sent" screen

Replace the static success illustration with HashBagSuccessAnimation: the money
sack sits at the bottom and #/$/₿ glyphs erupt from its mouth, rising and fading
on a loop. Glyphs are PNG assets (the app bundles no font with a ₿ glyph).

InfoPage gains an overridable buildIllustration() hook (default unchanged:
static HashImageWidget); only TransactionSuccessPage overrides it, so every
other InfoPage is untouched.

NOTE: written without a local Flutter build (Dart pub can't resolve here) —
verify on the next CI/device build. Self-contained and revertible; the static
hash_bag.png remains the fallback via imageLightPath/imageDarkPath.

lib/src/screens/Info_page.dart

@@ -21,6 +21,12 @@ abstract class InfoPage extends BasePage {
   Key? get buttonKey;
   void Function(BuildContext) get onPressed;
 
+  /// The illustration shown at the top of the page. Defaults to the static
+  /// image at [imageLightPath]/[imageDarkPath]; subclasses can override to
+  /// supply an animated widget instead.
+  Widget buildIllustration(BuildContext context, String image) =>
+      HashImageWidget(imageUrl: image);
+
   @override
   bool get gradientBackground => true;
 
@@ -56,7 +62,7 @@ abstract class InfoPage extends BasePage {
                   ),
                   child: AspectRatio(
                     aspectRatio: 0.9,
-                    child: HashImageWidget(imageUrl: image),
+                    child: buildIllustration(context, image),
                   ),
                 ),
               ),

lib/src/screens/send/transaction_success_info_page.dart

@@ -1,5 +1,6 @@
 import 'package:hash_wallet/generated/i18n.dart';
 import 'package:hash_wallet/src/screens/Info_page.dart';
+import 'package:hash_wallet/src/widgets/hash_bag_success_animation.dart';
 import 'package:flutter/cupertino.dart';
 
 class TransactionSuccessPage extends InfoPage {
@@ -11,6 +12,10 @@ class TransactionSuccessPage extends InfoPage {
 
   final String content;
 
+  @override
+  Widget buildIllustration(BuildContext context, String image) =>
+      const HashBagSuccessAnimation();
+
   @override
   bool get onWillPop => false;