fix(llmobs): don't drop IO annotations equal to zero (#11044) [backport 2.11]

[lievan]

Backport 2f23eb2 from #11044 to 2.11.

Fixes an issue where we are dropping I/O annotations that were equal to zero for workflow, task, agent and tool spans.

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• Newly-added code is easy to change

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• The change includes or references documentation updates if necessary

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• Title is accurate

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• Avoids breaking API changes

• Testing strategy adequately addresses listed risks

• Newly-added code is easy to change

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• If necessary, author has acknowledged and discussed the performance implications of this PR as reported in the benchmarks PR comment

• Backport labels are set in a manner that is consistent with the release branch maintenance
  policy

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Checklist

• PR author has checked that all the criteria below are met
• The PR description includes an overview of the change
• The PR description articulates the motivation for the change
• The change includes tests OR the PR description describes a testing strategy
• The PR description notes risks associated with the change, if any
• Newly-added code is easy to change
• The change follows the library release note guidelines
• The change includes or references documentation updates if necessary
• Backport labels are set (if applicable)

Reviewer Checklist

• Reviewer has checked that all the criteria below are met
• Title is accurate
• All changes are related to the pull request's stated goal
• Avoids breaking API changes
• Testing strategy adequately addresses listed risks
• Newly-added code is easy to change
• Release note makes sense to a user of the library
• If necessary, author has acknowledged and discussed the performance implications of this PR as reported in the benchmarks PR comment
• Backport labels are set in a manner that is consistent with the release branch maintenance policy

[github-actions]

CODEOWNERS have been resolved as:

releasenotes/notes/fix-numeric-annotations-7cf06b5ceb615282.yaml        @DataDog/apm-python
ddtrace/llmobs/_llmobs.py                                               @DataDog/ml-observability
tests/llmobs/test_llmobs_service.py                                     @DataDog/ml-observability

[datadog-dd-trace-py-rkomorn]

Datadog Report

Branch report: evan.li/backport-11044-2.11
Commit report: 300a7e9
Test service: dd-trace-py

✅ 0 Failed, 40455 Passed, 1441 Skipped, 34m 10.63s Total duration (2h 2m 39.15s time saved)
❄️ 1 New Flaky

New Flaky Tests (1)

• test_send_timed_events - test_llmobs_eval_metric_writer.py

[pr-commenter]

Benchmarks

Benchmark execution time: 2024-10-25 17:49:54

Comparing candidate commit 300a7e9 in PR branch evan.li/backport-11044-2.11 with baseline commit dc8591a in branch 2.11.

Found 0 performance improvements and 0 performance regressions! Performance is the same for 214 metrics, 2 unstable metrics.