chore(#214): bump version to 1.1.2-rc.2+59 for closed-test AAB

Cut v1.1.2-rc.2 (rc.1+46 -> rc.2+59). versionCode 59 clears the
b45-b58 GitHub test-build tags for a clean monotonic line ahead of
the first Google Play closed-test upload.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

pubspec.yaml

@@ -16,7 +16,7 @@ publish_to: 'none' # Remove this line if you wish to publish to pub.dev
 # https://developer.apple.com/library/archive/documentation/General/Reference/InfoPlistKeyReference/Articles/CoreFoundationKeys.html
 # In Windows, build-name is used as the major, minor, and patch parts
 # of the product and file versions while build-number is used as the build suffix.
-version: 1.1.2-rc.1+46
+version: 1.1.2-rc.2+59
 
 environment:
   sdk: ^3.9.2