feat(config): support libdatadog's library_config for config through file

[BaptisteFoy]

Description of changes

Most changes were taken from #11839

• Bumps libdatadog to v16.0.2
• Starts using the library_config component of libdatadog that allows reading configuration from a file with a higher precedence than environment variables

Supported config entries

As of libdatadog v16.0.2:

• DD_APM_TRACING_ENABLED
• DD_RUNTIME_METRICS_ENABLED
• DD_LOGS_INJECTION
• DD_PROFILING_ENABLED
• DD_DATA_STREAMS_ENABLED
• DD_APPSEC_ENABLED
• DD_IAST_ENABLED
• DD_DYNAMIC_INSTRUMENTATION_ENABLED
• DD_DATA_JOBS_ENABLED
• DD_APPSEC_SCA_ENABLED
• DD_TRACE_DEBUG
• DD_SERVICE
• DD_ENV
• DD_VERSION

Testing strategy

Added a unit test.

To test this PR, you can:

1. Create a Linux VM
2. Start this tracer version & ensure everything works well (non-regression)
3. Create a file at the following path: /etc/datadog-agent/application_monitoring.yaml
4. Write the following content in the file:

rules:
  - selectors:
      - origin: language
        matches:
          - python
        operator: equals
    configuration:
      DD_TRACE_DEBUG: true

5. Start this tracer version
6. Verify that debug logs are properly enabled

Additional concerns

Relevant system test: DataDog/system-tests#3982

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:

src/native/library_config.rs                                            @DataDog/apm-core-python
tests/internal/test_native.py                                           @DataDog/apm-core-python
ddtrace/__init__.py                                                     @DataDog/apm-core-python
ddtrace/internal/native/__init__.py                                     @DataDog/apm-core-python
ddtrace/internal/native/_native.pyi                                     @DataDog/apm-core-python
src/native/Cargo.lock                                                   @DataDog/apm-core-python
src/native/Cargo.toml                                                   @DataDog/apm-core-python
src/native/lib.rs                                                       @DataDog/apm-core-python

[datadog-dd-trace-py-rkomorn]

Datadog Report

Branch report: baptiste.foy/FA/library-config-libdatadog--2
Commit report: 14950cf
Test service: dd-trace-py

✅ 0 Failed, 130 Passed, 1184 Skipped, 3m 25.74s Total duration (25m 43.72s time saved)

[paullegranddc]

Ship it 🔥 🔥 🔥

[pr-commenter]

Benchmarks

Benchmark execution time: 2025-02-11 17:13:36

Comparing candidate commit 14950cf in PR branch baptiste.foy/FA/library-config-libdatadog--2 with baseline commit a604d93 in branch main.

Found 0 performance improvements and 1 performance regressions! Performance is the same for 393 metrics, 2 unstable metrics.

scenario:iast_aspects-ospathbasename_aspect

• 🟥 execution_time [+252.411ns; +299.090ns] or [+7.565%; +8.964%]