Add respectPrefersReducedMotion map option

[stepankuzmin]

Adds respectPrefersReducedMotion map option (true by default). If set to true, the map will respect the user's prefers-reduced-motion browser setting and apply a reduced motion mode, minimizing animations and transitions if it is set to reduce. When set to false, the map will always ignore the prefers-reduced-motion settings, regardless of the user's preference, making all animations essential.

respectPrefersReducedMotion.mov

See also #849, #8883, and #12631

Launch Checklist

• briefly describe the changes in this PR
• include before/after visuals or gifs if this PR includes visual changes
• write tests for all new functionality
• document any changes to public APIs
• manually test the debug page
• tagged @mapbox/gl-native if this PR includes shader changes or needs a native port
• apply changelog label ('bug', 'feature', 'docs', etc) or use the label 'skip changelog'
• add an entry inside this element for inclusion in the mapbox-gl-js changelog: <changelog>Add "respectPrefersReducedMotion" map option</changelog>

[rreusser]

Just saw this in passing, and on a subtle note I like the API naming, as opposed to a goofy three-state boolean prefersReducedMotion: true | false | null where null means unspecified and uses the browser setting. Will fall short of "approve" since just a drive-by review, but it does look good to me. 👍

[rreusser]

Is this deletion in passing of an unused property?

[stepankuzmin]

Yeah, that was accidentally added in #11524. We don't support offset in CameraOptions, so there is no way to use offset with jumpTo. One related thing I've stumbled on is #7902, but we can address it in a separate PR.