docs: remove redundant hosted tool search dependency floor

[jbeckwith-oai]

Summary

Remove the stale openai version floor from the hosted tool search documentation. Package installers already enforce the dependency constraint in pyproject.toml, so repeating it here creates a second value that can drift. Preserve the Responses-model requirement.

Test plan

• Reviewed the complete one-line diff against main and verified the dependency is declared in pyproject.toml.
• git diff --check passed.
• Editorial-only deletion; SDK tests and the documentation build are not required by the repository's editorial verification tier. Generated translations are left for regeneration.

Issue number

Fixes #5328

Checks

• I've added new tests, if relevant (not applicable: editorial documentation change)
• I've run .agents/skills/code-change-verification/scripts/run.sh (not required for editorial-only docs)
• I've confirmed all applicable verification steps pass
• If using Codex, I've run /review before submitting this PR (basic diff review completed; slash-command review not invoked)

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-10-07T14:13:58.049575Z	76d7181	PR opened
🔒 Security Review	✅ Completed 2026-10-07T14:13:33.453672Z	76d7181	PR opened

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[markstuart-oai]

Removing the duplicated version floor keeps the dependency requirement in pyproject.toml, which already requires openai>=3.0.0,<4 in both this revision and v0.23.1. The Responses-model restriction and tool setup guidance remain intact. No findings.

Reviewed the complete one-line change. Hosted CI for this commit passed, including the docs build and CodeQL; three packaged-contract jobs were skipped. No local SDK tests or builds were run.