chore!: move to typescript and vitest

[westeezy]

• Codebase is migrated to TypeScript by using https://github.com/Khan/flow-to-ts
• Dist folder now outputs esm folder
• Package.json update for types & modules
• Flowgen is used to generate flow types from dist/*.d.ts

[westeezy]

Published alpha: @krakenjs/[email protected]

dist
├── cross-domain-safe-weakmap.js
├── cross-domain-safe-weakmap.js.map
├── cross-domain-safe-weakmap.min.js
├── cross-domain-safe-weakmap.min.js.map
└── esm
    ├── index.d.ts
    ├── index.js
    ├── index.js.flow
    ├── native.d.ts
    ├── native.js
    ├── native.js.flow
    ├── util.d.ts
    ├── util.js
    ├── util.js.flow
    ├── weakmap.d.ts
    ├── weakmap.js
    └── weakmap.js.flow