docs: documet support for type aliases (#11117)

www/apps/book/app/learn/conventions/ts-aliases/page.mdx

@@ -0,0 +1,46 @@
+export const metadata = {
+  title: `${pageNumber} Using TypeScript Aliases`,
+}
+
+# {metadata.title}
+
+By default, Medusa doesn't support TypeScript aliases in production.
+
+If you prefer using TypeScript aliases, install following development dependencies:
+
+```bash npm2yarn
+npm install --save-dev tsc-alias rimraf
+```
+
+Where `tsc-alias` is a package that resolves TypeScript aliases, and `rimraf` is a package that removes files and directories.
+
+Then, add a new `resolve:aliases` script to your `package.json` and update the `build` script:
+
+```json title="package.json"
+{
+  "scripts": {
+    // other scripts...
+    "resolve:aliases": "tsc --showConfig -p tsconfig.json > tsconfig.resolved.json && tsc-alias -p tsconfig.resolved.json && rimraf tsconfig.resolved.json",
+    "build": "npm run resolve:aliases && medusa build"
+  }
+}
+```
+
+You can now use TypeScript aliases in your Medusa application. For example, add the following in `tsconfig.json`:
+
+```json title="tsconfig.json"
+{
+  "compilerOptions": {
+    // ...
+    "paths": {
+      "@/*": ["./src/*"]
+    }
+  }
+}
+```
+
+Now, you can import modules, for example, using TypeScript aliases:
+
+```ts
+import { BrandModuleService } from "@/modules/brand/service"
+```