Add onStartReached and sync onEndReached doc

[janicduplessis]

• Add docs for onStartReached for FlatList and SectionList
• Sync up docs with source code for onEndReached for FlatList and SectionList

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[Simek]

Refs:

• Add onStartReached and onStartReachedThreshold to VirtualizedList react-native#35321

Hey @janicduplessis, thank you for the followup on core PR! 👍

After looking at the code, I think it would be nice to clarify where exactly those propos are defined. By that I mean that the props should not be a part of FlatList and SectionList, but be listed in VirtualizedList props, which are than extended but listed earlier components. We already show the parent props link at the top of API documentation.

There were some concerns and benefits around duplicating props of parent in child components, it's fine to leave it as is for now since is a broader topic, but no matter which approach we choose, the VirtualizedList props also need to be updated:

• https://github.com/facebook/react-native-website/blob/main/docs/virtualizedlist.md

[janicduplessis]

@Simek Sounds good, I didn’t see that shared doc! Will move onStart/End there.

[janicduplessis]

@Simek Done!

[Simek]

LGTM, thank you for the updates! 👍

We can ship this since changes are already a part of upcoming 0.72 release, but let's wait for one more review, to make sure we are aligned on the approach.

[janicduplessis]

Ping @NickGerleman @cortinico

[Simek]

I have asked around, and it seems that people do not have a strong preference around that, let's ship this as is. We can always follow up with changes, if someone will find this pattern confusing/cumbersome. 🙂