Adding an overload of McpClientExtensions::CallToolAsync taking Dictionary<string, JsonElement> tool argument

[anuchandy]

Adding McpClientExtensions::CallToolAsync overload that takes tool parameters in the form Dictionary<string, JsonElement> .

Motivation and Context

Please see #640

How Has This Been Tested?

yes, and added the unit tests.

Breaking Changes

this is a non-breaking change.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation update

Checklist

• I have read the MCP Documentation
• My code follows the repository's style guidelines
• New and existing tests pass locally
• I have added appropriate error handling
• I have added or updated documentation as needed

Additional context

[eiriktsarpalis]

There are many ways in which you could represent tool arguments in STJ: IDictionary<string, JsonElement>, IDictionary<string, object?>, JsonElement, JsonObject, IReadOnlyDictionary<string, JsonNode?>, so singling out an overload for this particular representation feels oddly specific. Rather than exposing overloads for each and every one of them, I would be inclined to just ask users to populate the one representation picked by the library (or author extension methods that perform the conversion under wraps).