Enhance :focus-visible states color contrast

[ffoodd]

Our primary color #f16e00 leads to insufficient contrasts against #ffffff.

Thanks to the :focus-visible polyfill, we're now able to distinguish the focus state when using keyboard—which already got enhanced with outlines.

I suggest we go a step further by ensuring contrasts (mostly using a darker orange) for components using #f16e00 in either color or background-color when focused.

• inventory cases with #f16e00 when focused
• select the minimum viable orange: for now, $orange-700 which results in #a44b00, see current v5-dev deploy
• apply it in listed cases.