release: 3.19.0 (#325)

* feat(internal): implement indices array format for query and form serialization

* STG-1537 default local-mode sessions to local browser

* release: 3.19.0

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Co-authored-by: stainless-app[bot] <142633134+stainless-app[bot]@users.noreply.github.com>
Co-authored-by: monadoid <sam.finton@gmail.com>
Co-authored-by: Sam F <43347795+monadoid@users.noreply.github.com>