release: 2.45.0 (#3478)

* feat(api): gpt-5.6-sol updates

* fix(api): restore beta resource accessors

* chore: retrigger release automation

* release: 2.45.0

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Co-authored-by: stainless-app[bot] <142633134+stainless-app[bot]@users.noreply.github.com>
Co-authored-by: Alex Chang <apcha@openai.com>