Part of #4228

Migration guide: azure_core

Official Crate

• Name: azure_core
• Current version: 0.34.0
• Service: Core HTTP/retry/pipeline framework for all Azure SDK crates

Unofficial Predecessor(s)

Migration Guide Should Cover

• New pipeline model replacing the era 2 HTTP pipeline
• Redesigned Pager and Poller abstractions
• Pluggable async runtime support (no more hard Tokio dependency)
• Cloud configuration (CloudConfig) for sovereign clouds
• SecretBytes for credential handling
• HTTP logging with sanitization
• Sync response handling changes
• OpenTelemetry tracing macro integration
• Dependency version bumps and feature flag changes
• Migration path for azure_sdk_core users (start from scratch)

Acceptance Criteria

• Migration guide published in repo docs (e.g., docs/migration/azure_core.md)
• Code samples for key scenarios: creating a custom pipeline policy, using Pager/Poller, configuring cloud endpoints
• FAQ section covering common migration pitfalls
• Linked from the azure_core crate README
• Reviewed by SDK team