[Android] Add headers support when passing source array

[marcesengel]

Summary

Currently passing headers in the source array of an <ImageView /> is not supported on android because

• headers are passed to native via one ReadableMap prop, passed as-is to the ReactNetworkImageRequest.fromBuilderWithHeaders. This means different headers per array entry are simply not possible
• currently those headers are passed to native via source?.headers which clearly will not work when putting the headers into the source array (e.g. [ { headers: { Test: '123' }, uri: '...' } ] - this also showcases a workaround, just set the headers property on your source array and you are good to go as long as you always need the same headers)

Changelog

• Simplified android <Image /> code flow
• Moved android native image view headers property into the src property
• Added headers property to ImageSource class

[Android] [Fix] - Support headers when passing an array for the <Image /> source property

Test Plan

CI tests should cover these changes.

Edit: Also confirmed working in a test project.

[mikehardy]

Hopefully this is not irritating for them - but I requested review from @mdvacca and @yungsters - they appear to be the most recent editors in this area? Apologies in advance if that's a courtesy breach. Cheers all

[github-actions]

This PR is stale because it has been open 180 days with no activity. Remove stale label or comment or this will be closed in 7 days.

[marcesengel]

Not stale 😖