Add pre-configured code transform + Replace Vite Library Mode by raw Rollup

[nvh95]

Features

• Add pre-configured code transforms for css, file and fileCRA. Users don't need to update the configs when we ship a feature that requires adjusting the config.

transform: {
-  '^.+\\.css$': '<rootDir>/config/jest/cssTransform.js',
+  '^.+\\.css$': '<rootDir>/transforms/css',
-  '^(?!.*\\.(js|jsx|mjs|cjs|ts|tsx|json)$)': '<rootDir>/config/jest/fileTransform.js',
+  '^(?!.*\\.(js|jsx|mjs|cjs|ts|tsx|json)$)': '<rootDir>/transforms/file',
},

• Use Rollup instead of Vite Library Mode since Vite doesn't handle multiple entries well. I tried to overwrite Vite's build.lib config with rollupOptions but it doesn't work (and very bad DX). So I switch to rollup to meet jest-preview's need.
  • There is already a PR to support multiple entries for Vite Library Mode feat(lib): allow multiple entries vitejs/vite#7047. Will consider switching back to Vite if it gets merged.
  • Keep vite build commands as legacy

-"build::only": "vite build",
+"build:legacy::only": "vite build",
-"build:watch": "vite build --watch",
+"build:legacy:watch": "vite build --watch",

[ntt261298]

I think this should be jest-preview/transforms/fileCRA

[ntt261298]

This should be jest-preview/transforms/fileCRA right?