ref: Add cont profiling support to span first (19)

[sentrivana]

We'll only support continuous profiling in span first.

Note: Span-first profiling is not yet supported server-side.

[github-actions]

Semver Impact of This PR

🟢 Patch (bug fixes)

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[github-actions]

Codecov Results 📊

✅ 13 passed | Total: 13 | Pass Rate: 100% | Execution Time: 8.59s

All tests are passing successfully.

❌ Patch coverage is 20.00%. Project has 14260 uncovered lines.

Files with missing lines (1)

File	Patch %	Lines
traces.py	35.60%	⚠️ 199 Missing

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