feat(release): add Fairfax and Mooncake Managed SDP support

[zanejohnson-azure]

Summary

• replace the empty Escort JIT stage and public-cloud Fairfax registration with independent manual Fairfax and Mooncake Managed SDP stages
• select Prod, Fairfax, or Mooncake Ev2 configuration through $rolloutinfra() and bind the matching Arc registration endpoint
• add a sovereign stable-only registration payload plus a ValidateOnly pipeline parameter and fail-fast input validation

Deployment prerequisites

Before either sovereign stage can roll out successfully:

• Service Tree service 3170cdd2-19f0-4027-912b-1027311691a2 needs tenant-local owner groups in USME and CME; without them Approval Service fails during RegisterService
• Microsoft.Azure.SDP.Standard must be onboarded and available in Fairfax and Mooncake
• the configured Ev2 managed identity, admin subscription, ContainerInsights-30c56c3a-54da-46ea-b004-06eb33432687 subscription key, and Arc registration resource audience must be resolvable and authorized in each sovereign cloud

Managed SDP removes the pipeline-agent Escort JIT requirement once those pre-authorized sovereign identities and service registrations are in place.

Validation

• Azure DevOps definition 1031 previewRun expanded all stages with Fairfax, Mooncake, and ValidateOnly: true
• changed Ev2 JSON parsed successfully
• shell syntax and isolated Public/Fairfax/Mooncake request-generation tests passed

[github-actions]

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