feat(design, storefront)!: move `DaffQuantityFieldComponent` into the storefront package

[xelaint]

PR Checklist

• [x] Commit message follows our contributing guidelines
• [ ] Tests added/updated (for bug fixes/features)
• [ ] Documentation added/updated (for bug fixes/features)

PR Type

• [ ] Bug fix
• [x] Feature
• [ ] Style update
• [ ] Refactor
• [ ] Test
• [ ] Build
• [ ] CI
• [ ] Docs
• [ ] Performance
• [ ] Other (please describe)

Current behavior

Replace inputs with signals in order to handle focus changes.

Currently, focus does not transition when select changes to an input.

Fixes: #3888 Part of: #416, #3799

New behavior

Breaking change?

• [x] Yes
• [ ] No

BREAKING CHANGE: The quantity field component has been moved from @daffodil/design to @daffodil/storefront.

Additional context

[xelaint]

@damienwebdev moved quantity field to @daffodil/storefront. This is ready for final review.