ref(rust): Don't implement separate scope management

[sentrivana]

The Rust tracing integration is doing scope management on its own when it can just rely on the span API.

(This jumped out at me while resolving some mypy complaints on a span first PR.)

[github-actions]

Semver Impact of This PR

🟢 Patch (bug fixes)

📋 Changelog Preview

This is how your changes will appear in the changelog.
Entries from this PR are highlighted with a left border (blockquote style).

---

New Features ✨

• (crons) Add owner field to MonitorConfig by julwhitney13 in #5610
• (pydantic-ai) Add tool description to execute_tool spans by ericapisani in #5596

Bug Fixes 🐛

• (celery) Propagate user-set headers by sentrivana in #5581
• (utils) Avoid double serialization of strings in safe_serialize by ericapisani in #5587

Documentation 📚

• (openai-agents) Remove inapplicable comment by alexander-alderman-webb in #5495
• Add AGENTS.md by sentrivana in #5579
• Add set_attribute example to changelog by sentrivana in #5578

Internal Changes 🔧

Openai Agents

• Do not fail on new tool fields by alexander-alderman-webb in #5625
• Stop expecting a specific function name by alexander-alderman-webb in #5623
• Set streaming header when library uses with_streaming_response() by alexander-alderman-webb in #5583
• Replace mocks with httpx for streamed responses by alexander-alderman-webb in #5580
• Replace mocks with httpx in non-MCP tool tests by alexander-alderman-webb in #5602
• Replace mocks with httpx in MCP tool tests by alexander-alderman-webb in #5605
• Replace mocks with httpx in handoff tests by alexander-alderman-webb in #5604
• Replace mocks with httpx in API error test by alexander-alderman-webb in #5601
• Replace mocks with httpx in non-error single-response tests by alexander-alderman-webb in #5600
• Remove test for unreachable state by alexander-alderman-webb in #5584
• Expect namespace tool field for new openai versions by alexander-alderman-webb in #5599

Other

• (httpx) Resolve type checking failures by alexander-alderman-webb in #5626
• (pyramid) Support alpha suffixes in version parsing by alexander-alderman-webb in #5618

• (rust) Don't implement separate scope management by sentrivana in #5639

• Remove CodeQL action by sentrivana in #5616
• Normalize dots in package names in populate_tox.py by alexander-alderman-webb in #5574
• Do not run actions on potel-base by sentrivana in #5614

---

_{🤖 This preview updates automatically when you update the PR.}

[github-actions]

Codecov Results 📊

✅ 134 passed | Total: 134 | Pass Rate: 100% | Execution Time: 21.01s

All tests are passing successfully.

❌ Patch coverage is 0.00%. Project has 13427 uncovered lines.

Files with missing lines (1)

File	Patch %	Lines
rust_tracing.py	0.00%	⚠️ 135 Missing

---

Generated by Codecov Action