Build exchange workspace and shared transaction services (#28)

frontend/app/pubspec.yaml

@@ -6,6 +6,8 @@ environment:
   sdk: '>=3.13.0 <4.0.0'
   flutter: '>=3.47.0'
 dependencies:
+  sxchnge_wallet:
+    path: ../packages/sxchnge_wallet
   sxchnge_kyc:
     path: ../packages/sxchnge_kyc
   sxchnge_analytics: