Feature request: support cts and mts entry and generate dts file as is

[xiaoxiangmoe]

Describe the feature

repo: https://github.com/xiaoxiangmoe/issue-unbuild-mts-cts

in this repo, when we run yarn tsc-build, we will

• compile index.cts to tsc-cjs-dist/index.d.cts and tsc-cjs-dist/index.cjs
• compile index.mts to tsc-mjs-dist/index.d.mts and tsc-mjs-dist/index.mjs

.
├── package.json
├── src
│   ├── index.cts
│   ├── index.mts
│   └── plugin.ts
├── tsc-cjs-dist
│   ├── index.cjs
│   ├── index.d.cts
│   ├── plugin.d.ts
│   └── plugin.js
├── tsc-mjs-dist
│   ├── index.d.mts
│   ├── index.mjs
│   ├── plugin.d.ts
│   └── plugin.js
├── tsconfig.cjs.json
├── tsconfig.json
└── tsconfig.mjs.json

Can we change tsc to unbuild and bundle dist? The file structure I like is as follow.

.
├── build.config.ts
├── dist
│   ├── index.cjs
│   ├── index.d.cts
│   ├── index.d.mts
│   └── index.mjs
├── package.json
├── src
│   ├── index.cts
│   ├── index.mts
│   └── plugin.ts
├── tsconfig.cjs.json
├── tsconfig.json
└── tsconfig.mjs.json

Additional information

• Would you be willing to help implement this feature?

[pi0]

#273 (also unjs/mkdist#162)