Feat/custom component

[jeongshin]

Feature: add custom component support

Hi, thanks for great library.
I'd like to add support for custom react element support for images or other ui as mentioned on #2

I tested on iOS and Android and it look works fine.

{SpannableBuilder.getInstance($typo)
            .appendCustom('헉배', $typoPink)
            .append('님은 ')
            .appendCustom(`${cards.length}`, $number)
            .append(' 개 성공했어요! ')
            .appendCustomComponent(
              <FastImage
                source={{
                  uri: 'https://talkimg.imbc.com/TVianUpload/tvian/TViews/image/2023/04/27/0e83f60f-51d4-49b2-919c-92ec2ff928c5.jpg',
                }}
                style={{ width: 30, height: 30, borderRadius: 30 }}
              />,
            )
            .build()}

[mym0404]

I don't know about that how RN Text handles layout or lifecycle of children. But it seems working.

Thank you for change 🎉