feat: add image.verticalAlign option to htmlStyle

[fendent]

Summary

Adds an image.verticalAlign property to the htmlStyle prop that controls how inline image attachments are vertically positioned within the line.

• 'baseline' (default): existing behavior — image bottom aligns with the font descender
• 'bottom': image bottom aligns with the bottom of the line fragment

This is useful for chat-style inputs where inline emotes should sit flush with the text baseline rather than floating above it.

<EnrichedTextInput
  htmlStyle={{ image: { verticalAlign: 'bottom' } }}
/>

Test Plan

1. Insert an inline image with default htmlStyle — verify image bottom aligns with the descender (existing behavior)
2. Set htmlStyle={{ image: { verticalAlign: 'bottom' } }} — verify image bottom aligns with the bottom of the line fragment
3. Insert multiple images on the same line — verify consistent alignment
4. Verify the caret renders correctly next to images in both modes

Compatibility

OS	Implemented
iOS	✅
Android	❌

Checklist

• E2E tests are passing
• Required E2E tests have been added (if applicable)

[exploIF]

Hi, thanks so much for the contribution. Could you add screenshots/videos documenting your work? This is helpful for us to better understand introduced changes :)