Mjansrud csharp throw on any error

[wing328]

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Summary by cubic

Adds an opt-in throwOnAnyError option for C# RestSharp clients to surface deserialization and transport errors by throwing them, including when a Polly retry policy is used. Default stays off to preserve current behavior.

• New Features

  • New generator switch throwOnAnyError (restsharp only, default false); documented in csharp generator options.
  • When enabled: set RestClientOptions.ThrowOnAnyError = true and rethrow PolicyResult.FinalException in the retry path so errors reach callers and logs.
  • Sample config updated to include throwOnAnyError: true.

• Migration

  • To enable, add throwOnAnyError: true under additionalProperties in your config, or pass --additional-properties throwOnAnyError=true.
  • No changes needed if you want to keep the current null-on-error behavior.

^{Written for commit 13e4897. Summary will update on new commits.}