feat: add paragraphSpacing to checkbox list (iOS + Android)

[ErionTp]

Summary

• Adds a paragraphSpacing property to ulCheckbox in HtmlStyle to control vertical spacing between checkbox list items
• iOS: Uses NSMutableParagraphStyle.paragraphSpacing which was already available in the native layer but not wired up
• Android: Extends EnrichedCheckboxListSpan.chooseHeight() to increase fm.descent/fm.bottom after the last line of each paragraph
• Defaults to 0 so existing behavior is unchanged

Usage

<EnrichedTextInput
  htmlStyle={{
    ulCheckbox: {
      paragraphSpacing: 6,
    },
  }}
/>

Changes

JS Layer (3 files):

• src/types.ts — Added paragraphSpacing?: number to ulCheckbox
• src/spec/EnrichedTextInputNativeComponent.ts — Added paragraphSpacing?: Float to native ulCheckbox
• src/utils/normalizeHtmlStyle.ts — Added paragraphSpacing: 0 default

iOS Native (4 files):

• ios/config/InputConfig.h — Declared checkboxListParagraphSpacing getter/setter
• ios/config/InputConfig.mm — Added ivar, copy, getter/setter
• ios/styles/CheckboxListStyle.mm — Set pStyle.paragraphSpacing when adding/removing checkbox attributes
• ios/EnrichedTextInputView.mm — Read new prop and apply to config

Android (3 files):

• android/.../EnrichedStyle.kt — Added ulCheckboxParagraphSpacing to interface
• android/.../EnrichedCheckboxListSpan.kt — Extended chooseHeight() to add spacing after last line of paragraph
• android/.../HtmlStyle.kt — Added property, parsing, equals(), hashCode()

Notes

• No breaking changes — defaults to 0
• Tested on iOS with Expo SDK 55

🤖 Generated with Claude Code

[szydlovsky]

Hey! Sorry that we're seeing this PR only now.

Looks like a nice thing to have BUT I think it's too narrow if we want to control paragraphSpacing only after the checkboxLists - there's no reason to have it only there. Ideally we want to control it for each paragraph, which suggests having it as a standalone style, something like recently added textAlignment.

[szydlovsky]

Having said that, we'll discuss it with the rest of the team 👍