ref: Add streaming trace decorator (7)

[sentrivana]

Description

Add the streaming equivalent of the @trace decorator.

Issues

Reminders

• Please add tests to validate your changes, and lint your code using tox -e linters.
• Add GH Issue ID & Linear ID (if applicable)
• PR title should use conventional commit style (feat:, fix:, ref:, meta:)
• For external contributors: CONTRIBUTING.md, Sentry SDK development docs, Discord community

[github-actions]

Semver Impact of This PR

🟢 Patch (bug fixes)

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Bug Fixes 🐛

• (celery) Propagate user-set headers by sentrivana in #5581

Documentation 📚

• Add AGENTS.md by sentrivana in #5579
• Add set_attribute example to changelog by sentrivana in #5578

Internal Changes 🔧

• Add streaming trace decorator (7) by sentrivana in #5594

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[github-actions]

Codecov Results 📊

✅ 13 passed | Total: 13 | Pass Rate: 100% | Execution Time: 7.01s

All tests are passing successfully.

❌ Patch coverage is 17.50%. Project has 13855 uncovered lines.

Files with missing lines (2)

File	Patch %	Lines
tracing_utils.py	43.69%	⚠️ 348 Missing and 28 partials
traces.py	51.70%	⚠️ 71 Missing

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Generated by Codecov Action

[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

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[cursor]

Context manager __enter__ doesn't register span as active

Medium Severity

StreamedSpan.__enter__ just returns self without setting the span as the active span on the scope. The existing Span.__enter__ in tracing.py does scope.span = self so that nested spans can discover their parent. Without this, create_streaming_span_decorator's with start_streaming_span(...) never makes the span visible to the scope, so nested @trace-decorated functions each create independent root spans instead of forming a parent-child tree. The corresponding __exit__ also doesn't restore the previous span or set error status on exceptions, unlike the analogous Span.__exit__.

Additional Locations (1)

• sentry_sdk/tracing_utils.py#L958-L981