Allow passing soroban_models.Parameters directly to invoke

Author: tupui

README.md

@@ -46,7 +46,7 @@ import json
 import soroban
 
 args = json.load(...)
-args = soroban.Parameters(args=args).model_dump()
+args = soroban.Parameters(args=args)
 soroban.invoke(contract_id="AAAA...", function_name="init", args=args)
 ```
 

src/soroban/invoke.py

@@ -47,6 +47,7 @@ def invoke(
         if isinstance(network, soroban_models.NetworkConfig)
         else soroban_models.NetworkConfig.from_network(network=network)
     )
+    args = args.model_dump() if isinstance(args, soroban_models.Parameters) else args
 
     soroban_server = stellar_sdk.SorobanServer(network.rpc_url)
     source_account_ = soroban_server.load_account(identity.public_key)