fix(durablejobs): preserve trace context on retry

[ReubenBond]

Durable job retries reconstructed the queued job without copying its persisted W3C trace context. When an attempt was retried, subsequent execution therefore started a new trace and caused the tracing continuity test to fail under load.\n\nPreserve both traceparent and tracestate when rescheduling an in-memory job, with a focused regression test for retry context preservation.

Microsoft Reviewers: Open in CodeFlow

[Copilot]

Pull request overview

This PR fixes a tracing continuity bug in the durable jobs in-memory queue by ensuring W3C trace context (both traceparent and tracestate) is preserved when a queued job is rescheduled for retry. This aligns retry behavior with the persisted job data so subsequent attempts continue the original distributed trace.

Changes:

• Copy TraceParent and TraceState when reconstructing a job during RetryJobLater rescheduling.
• Add a focused regression test to verify trace context is preserved across retry rescheduling.
• Extend the test helper CreateJob to allow specifying trace context fields.

Show a summary per file

File	Description
src/Orleans.DurableJobs/InMemoryJobQueue.cs	Preserves TraceParent/TraceState when rebuilding a job during retry rescheduling.
test/Orleans.Core.Tests/DurableJobs/InMemoryJobQueueTests.cs	Adds regression coverage for trace context preservation and updates the job factory helper to set trace fields.

Copilot's findings

• Files reviewed: 2/2 changed files
• Comments generated: 0