feat(profiling): gevent support

[P403n1x87]

We add support for gevent in stack-v2.

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:

ddtrace/profiling/_gevent.py                                            @DataDog/profiling-python
ddtrace/internal/datadog/profiling/stack_v2/CMakeLists.txt              @DataDog/profiling-python
ddtrace/internal/datadog/profiling/stack_v2/include/sampler.hpp         @DataDog/profiling-python
ddtrace/internal/datadog/profiling/stack_v2/src/sampler.cpp             @DataDog/profiling-python
ddtrace/internal/datadog/profiling/stack_v2/src/stack_v2.cpp            @DataDog/profiling-python
ddtrace/profiling/collector/_task.pyx                                   @DataDog/profiling-python
tests/profiling/collector/test_task.py                                  @DataDog/profiling-python

[github-actions]

Bootstrap import analysis

Comparison of import times between this PR and base.

Summary

The average import time from this PR is: 236 ± 2 ms.

The average import time from base is: 238 ± 2 ms.

The import time difference between this PR and base is: -1.72 ± 0.1 ms.

Import time breakdown

The following import paths have shrunk:

ddtrace.auto 1.959 ms (0.83%)

ddtrace.bootstrap.sitecustomize 1.286 ms (0.54%)

ddtrace.bootstrap.preload 1.286 ms (0.54%)

ddtrace.internal.products 1.286 ms (0.54%)

ddtrace.internal.remoteconfig.client 0.633 ms (0.27%)

ddtrace 0.674 ms (0.29%)

[pr-commenter]

Benchmarks

Benchmark execution time: 2025-04-29 15:35:12

Comparing candidate commit 9bdf029 in PR branch profiling/gevent-support with baseline commit 5c7228a in branch main.

Found 0 performance improvements and 0 performance regressions! Performance is the same for 499 metrics, 9 unstable metrics.