release: 1.21.0 (#376)

* chore(internal): change default timeout to an int (#375)

* chore(internal): bummp ruff dependency (#377)

* feat(client): send `X-Stainless-Read-Timeout` header (#379)

* chore(internal): fix type traversing dictionary params (#380)

* chore(internal): minor type handling changes (#381)

* feat(api): Update schema for logprobs (#382)

* codegen metadata

* release: 1.21.0

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