feat: delegate agent project ownership to projects

[Hui Miao (huimiu)]

Why this is needed

Agent initialization and deployment need to create or reuse a Foundry project, but project ownership and lifecycle belong in the azure.ai.projects extension. Delegating those operations keeps azure.ai.agents focused on agent-specific resources while Projects owns project provisioning, environment setup, and managed deployment reconciliation.

Why this approach

Agents invokes Projects through the existing WorkflowService.Run boundary with a versioned, owner-only request.json. Projects reports workflow completion only; after success, Agents rereads Project and Environment state through the existing APIs and validates the unique project service and deployment signals it needs. There is no result.json or protobuf wire-detail dependency, so the layer remains compatible with the existing core API while preserving cancellation, gRPC status, and legacy fallback behavior.

This is the second layer and targets hui/foundry-projects-ownership from PR #9511. PR #9510 is not a prerequisite.

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[microsoft-github-policy-service]

Hi @Hui Miao (@huimiu). Thank you for your interest in helping to improve the Azure Developer CLI experience and for your contribution. We've noticed that there hasn't been recent engagement on this pull request. If this is still an active work stream, please let us know by pushing some changes or leaving a comment. Otherwise, we'll close this out in 7 days.