docs: add experimentalOptimizer?.[mode] documentation (#3526)

docs/config/index.md

@@ -109,25 +109,25 @@ Handling for dependencies resolution.
 
 #### deps.experimentalOptimizer
 
-- **Type:** `DepOptimizationConfig & { enabled: boolean }`
+- **Type:** `{ ssr?, web? }`
 - **Version:** Since Vitest 0.29.0
 - **See also:** [Dep Optimization Options](https://vitejs.dev/config/dep-optimization-options.html)
 
 Enable dependency optimization. If you have a lot of tests, this might improve their performance.
 
-For `jsdom` and `happy-dom` environments, when Vitest will encounter the external library, it will be bundled into a single file using esbuild and imported as a whole module. This is good for several reasons:
+When Vitest encounters the external library listed in `include`, it will be bundled into a single file using esbuild and imported as a whole module. This is good for several reasons:
 
 - Importing packages with a lot of imports is expensive. By bundling them into one file we can save a lot of time
 - Importing UI libraries is expensive because they are not meant to run inside Node.js
 - Your `alias` configuration is now respected inside bundled packages
 - Code in your tests is running closer to how it's running in the browser
 
-Be aware that only packages in `deps.experimentalOptimizer.include` option are bundled (some plugins populate this automatically, like Svelte). You can read more about available options in [Vite](https://vitejs.dev/config/dep-optimization-options.html) docs.
+Be aware that only packages in `deps.experimentalOptimizer?.[mode].include` option are bundled (some plugins populate this automatically, like Svelte). You can read more about available options in [Vite](https://vitejs.dev/config/dep-optimization-options.html) docs. By default, Vitest uses `experimentalOptimizer.web` for `jsdom` and `happy-dom` environments, and `experimentalOptimizer.ssr` for `node` and `edge` environments, but it is configurable by [`transformMode`](#transformmode).
 
-This options also inherits your `optimizeDeps` configuration. If you redefine `include`/`exclude` option in `deps.experimentalOptimizer` it will extend your `optimizeDeps` when running tests. Vitest automatically removes the same options from `include`, if they are listed in `exclude`.
+This options also inherits your `optimizeDeps` configuration (for web Vitest will extend `optimizeDeps`, for ssr - `ssr.optimizeDeps`). If you redefine `include`/`exclude` option in `deps.experimentalOptimizer` it will extend your `optimizeDeps` when running tests. Vitest automatically removes the same options from `include`, if they are listed in `exclude`.
 
 ::: tip
-You will not be able to edit your `node_modules` code for debugging, since the code is actually located in your `cacheDir` or `test.cache.dir` directory. If you want to debug with `console.log` statements, edit it directly or force rebundling with `deps.experimentalOptimizer.force` option.
+You will not be able to edit your `node_modules` code for debugging, since the code is actually located in your `cacheDir` or `test.cache.dir` directory. If you want to debug with `console.log` statements, edit it directly or force rebundling with `deps.experimentalOptimizer?.[mode].force` option.
 :::
 
 #### deps.external