[Bug]: TaskState enum in specification differs in JSON-RPC vs. gRPC

[jocelynh-microsoft]

What happened?

In the a2a specification, section 6.3, the enum for TaskState differs between JSON-RPC and gRPC:

• JSON-RPC has Unknown, gRPC has Unspecified
• JSON-RPC has Canceled (US spelling), gRPC has Cancelled (UK spelling)

Relevant log output

Code of Conduct

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[darrelmiller]

This has been addressed in this PR #1160 see https://purple-moss-0838db51e.3.azurestaticapps.net/specification/#413-taskstate for rendering.