fix(profiling): make explicitly marked main packages "my code"

[nsrip-dd]

If a user runs their code as a "main module" which they installed like a
library (python -m my_program args...), and expicilty specifies that
it's the main package via DD_MAIN_PACKAGE, we should consider code from
that module "my code". Right now we don't, though, because we mark that
code as a "library" in the profiling code provenance info. Check
whether the user specified a main package and make sure it gets marked
as "my code" by leaving the kind blank.

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/internal/datadog/profiling/code_provenance.py                   @DataDog/profiling-python
tests/profiling_v2/test_code_provenance.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: 279 ± 2 ms.

The average import time from base is: 282 ± 3 ms.

The import time difference between this PR and base is: -2.0 ± 0.1 ms.

Import time breakdown

The following import paths have shrunk:

ddtrace.auto 1.975 ms (0.71%)

ddtrace.bootstrap.sitecustomize 1.301 ms (0.47%)

ddtrace.bootstrap.preload 1.301 ms (0.47%)

ddtrace.internal.remoteconfig.client 0.639 ms (0.23%)

ddtrace 0.674 ms (0.24%)

ddtrace.internal._unpatched 0.029 ms (0.01%)

json 0.029 ms (0.01%)

json.decoder 0.029 ms (0.01%)

re 0.029 ms (0.01%)

enum 0.029 ms (0.01%)

types 0.029 ms (0.01%)

[pr-commenter]

Benchmarks

Benchmark execution time: 2025-06-11 18:38:55

Comparing candidate commit 354e1d1 in PR branch push-xtxtmqtxtxny with baseline commit 55e0c06 in branch main.

Found 0 performance improvements and 2 performance regressions! Performance is the same for 563 metrics, 7 unstable metrics.

scenario:telemetryaddmetric-1-distribution-metric-1-times

• 🟥 execution_time [+307.284ns; +366.095ns] or [+10.437%; +12.434%]

scenario:telemetryaddmetric-1-gauge-metric-1-times

• 🟥 execution_time [+240.314ns; +288.065ns] or [+11.028%; +13.220%]

[P403n1x87]

should we remove main_package from libraries instead of doing a ternary in a loop?