Epic: Pure Black Theme and Provider

[georgewrmarshall]

Description

Track implementation of Pure Black Theme and Provider across the MetaMask Design System.

This epic mirrors Jira TMCU-622.

Shared constraint (all child issues)

• isPureBlack=false uses the existing grey dark theme
• isPureBlack=true uses pureBlackDarkTheme

Child issues

• Add pureBlackDarkTheme to @metamask/design-tokens #1272 Add pureBlackDarkTheme to @metamask/design-tokens
• Add shared pure-black provider contract to @metamask/design-system-shared #1273 Add shared pure-black provider contract to @metamask/design-system-shared
• Add pure-black support to @metamask/design-system-twrnc-preset ThemeProvider #1274 Add pure-black support to @metamask/design-system-twrnc-preset ThemeProvider
• Add PureBlackProvider and usePureBlack to @metamask/design-system-react #1275 Add PureBlackProvider and usePureBlack to @metamask/design-system-react
• Adopt pure-black surface elevation behavior in MMDS components #1276 Adopt pure-black surface elevation behavior in MMDS components
• Update ModalContent for pure-black elevated surface #1280 Update ModalContent for pure-black elevated surface (depends on Add PureBlackProvider and usePureBlack to @metamask/design-system-react #1275)
• Update BottomSheetDialog for pure-black elevated surface #1281 Update BottomSheetDialog for pure-black elevated surface (depends on Add pure-black support to @metamask/design-system-twrnc-preset ThemeProvider #1274)
• Add design-token shadow utilities to @metamask/design-system-twrnc-preset #1288 Add design-token shadow utilities to @metamask/design-system-twrnc-preset
• Add pure-black POC to apps/storybook-react #1277 Add pure-black POC to apps/storybook-react
• Add pure-black POC to apps/storybook-react-native #1278 Add pure-black POC to apps/storybook-react-native
• Add validation coverage for pure-black theme and provider flow #1279 Add validation coverage for pure-black theme and provider flow