CW-608-Fetch-And-Save-Icons-Of-ERC20-And-SPL-Tokens-When-Adding-Them (#1365)

* feat: Fetch and save icons of SPL tokens when adding them

* feat: Implement fetch and save icons for ERC20 tokens when adding them

* fix: Add moralisApiKey to evm secrets

* Add check to ensure decimals cannot be zero

* - Fallback to adding erc20 token from web3dart
- Wrap fetching spl token icon in a try/catch block

---------

Co-authored-by: OmarHatem <omarh.ismail1@gmail.com>

cw_solana/lib/solana_client.dart

@@ -533,4 +533,21 @@ class SolanaWalletClient {
       throw Exception(e);
     }
   }
+
+  Future<String?> getIconImageFromTokenUri(String uri) async {
+    try {
+      final response = await httpClient.get(Uri.parse(uri));
+
+      final jsonResponse = json.decode(response.body) as Map<String, dynamic>;
+
+      if (response.statusCode >= 200 && response.statusCode < 300) {
+        return jsonResponse['image'];
+      } else {
+        return null;
+      }
+    } catch (e) {
+      print('Error occurred while fetching token image: \n${e.toString()}');
+      return null;
+    }
+  }
 }