Try to make JSON implementations work the same

[twogood]

No description provided.

[Copilot]

Pull Request Overview

This PR standardizes JSON serialization behavior between System.Text.Json and Newtonsoft.Json implementations to make them work consistently. The changes focus on aligning property naming conventions and null value handling across both JSON libraries.

• Removes camelCase naming policy from System.Text.Json defaults to match PascalCase used by Newtonsoft.Json
• Updates null value handling configuration to be consistent between implementations
• Simplifies test code by removing implementation-specific JSON content generation

Reviewed Changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
SystemTextJsonDefaults.cs	Changes default naming policy from camelCase to null and null handling from ignore to never
NewtonsoftJsonDefaults.cs	Adds camelCase contract resolver configuration
RestClientTests.cs	Adds null value handling parameter and refactors JSON serialization tests
SimpleValueObjectTest.cs	Removes implementation-specific JSON content generation in favor of hardcoded strings
RestClientTests.cs (Newtonsoft)	Simplifies test code by removing variables and using inline values
SimpleValueObjectTest.cs (System.Text.Json)	Updates property names from camelCase to PascalCase

Comments suppressed due to low confidence (1)

Activout.RestClient.Newtonsoft.Json/NewtonsoftJsonDefaults.cs:17

• [nitpick] The field name 'CamelCasePropertyNamesContractResolver' is redundant since DefaultContractResolver with CamelCaseNamingStrategy already indicates its purpose. Consider renaming to 'CamelCaseContractResolver' for brevity.

    public static readonly DefaultContractResolver CamelCasePropertyNamesContractResolver = new DefaultContractResolver