[Docs] Badge family migration documentation (5 components)

## Summary

Add migration documentation for the Badge component family (5 components) that have been migrated from Extension/Mobile to MMDS.

## Components

- BadgeWrapper
- BadgeIcon
- BadgeCount
- BadgeNetwork
- BadgeStatus

## Definition of Done

### 1. MIGRATION.md Sections
Add migration sections with API maps to:
- `packages/design-system-react/MIGRATION.md`
- `packages/design-system-react-native/MIGRATION.md`

Include:
- Breaking changes between Extension/Mobile and MMDS
- Prop mapping tables
- Before/after code examples

### 2. README Links
Add migration section to each component's README.mdx:
- Link to relevant MIGRATION.md section

### 3. @deprecated Updates
Add migration links to JSDoc in:
- Extension: `ui/components/component-library/badge*`
- Mobile: `app/component-library/components/Badge*`

## Example Reference
Text component migration: https://github.com/MetaMask/metamask-design-system/blob/main/packages/design-system-react/MIGRATION.md#text-component

## Labels
documentation

Start with the Text component migration section in packages/design-system-react/MIGRATION.md and inspect the corresponding design-system-react-native/MIGRATION.md structure. Locate the five Badge component README.mdx files and the Extension ui/components/component-library/badge* and Mobile app/component-library/components/Badge* JSDoc. Done means both migration guides contain API maps, breaking changes, prop tables, and examples, with README and @deprecated links added.

Written by the indexing model from the issue text.