trace headers for remote-write, Loki, etc.

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trafficstars

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Describe the issue you're reporting

I don't know if middleware would be where this is found, or how this would work.

I'm experiencing occasional difficulty with out-of-order samples using remote-write against Thanos. It would be helpful if I could pass in the trace headers because I do have Tempo collecting traces from all the Thanos components. Similarly, I'd like the same capability with Loki. I don't know if Tempo supports its own tracing, but anyway- is there a way to cause otel-collector to generate Trace IDs for itself and hand them upstream?