Update manual_instrumentation.md adding .Net entry

[gitstevenpham]

What does this PR do? What is the motivation?

Adds .Net entry based on https://dd.slack.com/archives/C05C61J554L/p1738011042428139

Merge instructions

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• Ready for merge

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Additional notes

[github-actions]

Preview links (active after the build_preview check completes)

Modified Files

• https://docs-staging.datadoghq.com/steven.pham/dotnet-entry-manual-instrumentation/data_streams/manual_instrumentation

[vandonr]

maybe we want to mention that doing that will also propagate the trace context ?
We could also link to the doc explaining how to trace propagate without DSM, which also has some nice examples of header getter/setter methods for some queues.

I'd even link in the other direction, from that doc linked above to here, like "hey, I see you want to inject trace context, how about injecting DSM at the same time ?"

[vandonr]

I wonder if this wording is not too strong... It will work, it's just that context is broken/lost on a send following a receive. I don't know how to convey that in a clear way.

[gitstevenpham]

How does:

Note: In async operations, this may not work as expected because the context derived from the incoming message can be lost when producing a new message in different threads.

Sound?

[gitstevenpham]

maybe we want to mention that doing that will also propagate the trace context ? We could also link to the doc explaining how to trace propagate without DSM, which also has some nice examples of header getter/setter methods for some queues.

I'd even link in the other direction, from that doc linked above to here, like "hey, I see you want to inject trace context, how about injecting DSM at the same time ?"

Added "The following example propogates the trace context. See Trace Context Propagation on how this is done in general."

[buraizu]

Requesting some minor edits

[gitstevenpham]

@buraizu can you help with the linking. I can't seem to get it to work

[johannbotha]

LGTM

[gitstevenpham]

/merge

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2025-02-07 15:56:48 UTC ℹ️ MergeQueue: pull request added to the queue

The median merge time in master is 7m.

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2025-02-07 16:04:54 UTC ℹ️ MergeQueue: This merge request was merged