docs: schema.json in node_modules (#9832)

### Description

Documenting `schema.json` availability in `node_modules` starting in
2.4.

### Testing Instructions

👀

---------

Co-authored-by: Chris Olszewski <chris.olszewski@vercel.com>

docs/repo-docs/getting-started/editor-integration.mdx

@@ -13,22 +13,43 @@ Turborepo uses [JSON Schema](https://json-schema.org/) to give you auto-complete
 `turbo.json` file. By including the `$schema` key in your `turbo.json`, your editor is able to
 provide full documentation and linting in case you have invalid shapes or missing keys.
 
+### Sourcing from the web
+
+A `schema.json` is accessible at the URL shown below. This has the advantage of not needing to run your package manager's install command to see in-editor validation.
+
 ```json title="./turbo.json"
 {
   "$schema": "https://turbo.build/schema.json"
 }
 ```
 
-### Older versions
-
-If you are using Turborepo v1, use `schema.v1.json`.
+There is also a major versioned `schema.json` available, following the format of `https://turbo.build/schema.<version>.json`.
 
 ```json title="./turbo.json"
 {
   "$schema": "https://turbo.build/schema.v1.json"
 }
 ```
 
+### Sourcing from `node_modules`
+
+Starting in Turborepo 2.4, `schema.json` is available in `node_modules` once you've run your package manager's install command:
+
+```json title="turbo.json"
+{
+  "$schema": "./node_modules/turbo/schema.json"
+}
+```
+
+<Callout title="node_modules location">
+  We recommend installing `turbo` at the root of your repository, so the path
+  for the schema should point to `node_modules` at the root of your repository.
+  In [Package Configurations](/repo/docs/reference/package-configurations), you
+  may need to use a path like `../../node_modules/turbo/schema.json`.
+</Callout>
+
+## Linting for environment variables
+
 Handling environment variables is an important part of building applications in a Turborepo.
 
 [The `eslint-config-turbo` package](/repo/docs/reference/eslint-config-turbo) extends your ESLint setup to help you make sure you've taken care of all of your environment variables.