Generate IDisposable Refit Interfaces

[christianhelle]

The changes here fixes the issue introduced in #541 where the generated code using IDisposable doesn't build due to the System namespace being imported multiple times.

This pull request includes several updates to documentation, configuration files, and code to support new features and improve existing functionality. The most important changes include the addition of polymorphic serialization and disposable client generation, along with corresponding updates to documentation and tests.

New Features:

• Added support for System.Text.Json polymorphic serialization, replacing NSwag JsonInheritanceConverter attributes with System.Text.Json JsonPolymorphicAttributes. This allows for native support of inheritance (de)serialization and fallback to base types when payloads with unknown types are offered by newer API versions. (README.md, cli-tool.md, json-schema.json, GenerateCommand.cs) [1] [2] [3] [4]
• Introduced the option to generate Refit clients that implement IDisposable, enabling better resource management. (README.md, cli-tool.md, json-schema.json, GenerateCommand.cs) [1] [2] [3] [4]

Documentation Updates:

• Updated the README.md files and other documentation to reflect the new options for polymorphic serialization and disposable client generation. (README.md, cli-tool.md, refitter-file-format.md) [1] [2] [3]
• Added examples and explanations for the new features in the .refitter file format and CLI tool documentation. (refitter-file-format.md, cli-tool.md) [1] [2]

Codebase Enhancements:

• Modified the RefitInterfaceImports.cs to conditionally include the System namespace only if disposable clients are generated. (RefitInterfaceImports.cs)
• Updated the GenerateCommand.cs to include the new GenerateDisposableClients setting. (GenerateCommand.cs)

Testing Improvements:

• Added new test cases to verify the generation of disposable clients and ensure the generated code builds correctly. (SwaggerPetstoreMultipleFileTests.cs, SwaggerPetstoreTests.cs) [1] [2]

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 94.76%. Comparing base (0cb3f2e) to head (515f15e).
Report is 11 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #543      +/-   ##
==========================================
+ Coverage   91.72%   94.76%   +3.03%     
==========================================
  Files          51       51              
  Lines        2659     2541     -118     
==========================================
- Hits         2439     2408      -31     
+ Misses        182       98      -84     
+ Partials       38       35       -3     

Flag	Coverage Δ
unittests	94.76% <100.00%> (+3.03%)	⬆️

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