fix(typescript-sdk): add workflow span fallback for dashboard-triggered runs

[onthebed]

Dashboard-triggered runs arrive at the worker with a propagated traceparent, but no exported producer span from the TS SDK side. That left step spans attached to a missing parent and the workflow envelope never showed up in traces.

This adds a worker-side hatchet.workflow_run fallback span when a valid upstream trace context exists but the metadata was not marked as coming from an SDK-exported trigger span. SDK-triggered runs still use their existing producer spans because instrumented trigger paths now mark the injected metadata before the worker sees it.

Verification:

• pnpm test:unit -- --runInBand src/opentelemetry/instrumentor.test.ts
• pnpm lint:check && npx tsc
• pnpm test:unit is still noisy in this environment because unrelated admin-client tests hit local gRPC connection failures (ECONNREFUSED 127.0.0.1:50051).

Fixes #3706

[vercel]

@onthebed is attempting to deploy a commit to the Hatchet Team on Vercel.

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[mrkaye97]

hi @onthebed, thanks for the contribution! I'd like a little more context here: If you're triggering from the dashboard, why would there be a parent span from the SDK? The SDK doesn't know anything about this run until it lands on a worker