Honor user-provided Json IContractResolver while maintaining marshaling capabilities

[matteo-prosperi]

Addressing failures similar to

StreamJsonRpc.RemoteMethodNotFoundException : Unable to find method 'xxx' on {no object} for the following reasons: Deserializing JSON-RPC argument with name "observer" and position 1 to type "xxx" failed: Could not create an instance of type xxx. Type is an interface or abstract class and cannot be instantiated. Path 'params[1].__jsonrpc_marshaled'.

when calling APIs under the following conditions:

• using Newtonsoft.Json
• the API has marshalable (IObserver<>, IDisposable or interfaces with RpcMarshalableAttribute) objects as parameters or return values
• the user replaces JsonMessageFormatter's ContractResolver.

This issue has worsened since #777 due to more behavior being delegated to the ContractResolver

This PR integrates the ContractResolver provided by the user with MarshalContractResolver before the first serialization or deserialization.

[codecov-commenter]

Codecov Report

Merging #783 (91adfe6) into main (381dbe8) will increase coverage by 0.04%.
The diff coverage is 100.00%.

❗ Current head 91adfe6 differs from pull request most recent head 8110046. Consider uploading reports for the commit 8110046 to get more accurate results

@@            Coverage Diff             @@
##             main     #783      +/-   ##
==========================================
+ Coverage   91.81%   91.86%   +0.04%     
==========================================
  Files          61       61              
  Lines        5342     5360      +18     
==========================================
+ Hits         4905     4924      +19     
+ Misses        437      436       -1     

Impacted Files	Coverage Δ
src/StreamJsonRpc/JsonMessageFormatter.cs	91.57% <100.00%> (+0.23%)	⬆️
src/StreamJsonRpc/MessageHandlerBase.cs	95.18% <0.00%> (-1.21%)	⬇️
src/StreamJsonRpc/JsonRpc.cs	94.03% <0.00%> (+0.26%)	⬆️

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