fix(medusa): normalize build path (#8166)

packages/medusa/src/commands/build.ts

@@ -1,6 +1,6 @@
 import { ConfigModule } from "@medusajs/types"
-import { transformFile } from "@swc/core"
 import { getConfigFile } from "@medusajs/utils"
+import { transformFile } from "@swc/core"
 import { existsSync } from "node:fs"
 import { copyFile, mkdir, readdir, rm, writeFile } from "node:fs/promises"
 import path from "path"
@@ -56,7 +56,7 @@ const getOutputPath = (file: string, config: FileConfig) => {
     outputPath = outputPath.replace(currentExtension, targetExtension)
   }
 
-  return outputPath
+  return outputPath.replaceAll(path.sep, "/")
 }
 
 const writeToOut = async (
@@ -72,9 +72,8 @@ const writeToOut = async (
 
 async function copyToOut(file: string, config: FileConfig) {
   const outputPath = getOutputPath(file, config)
-  const dirNameRegex = new RegExp("\\" + path.sep + "([^\\" + path.sep + "]+)$")
 
-  await mkdir(outputPath.replace(dirNameRegex, ""), { recursive: true })
+  await mkdir(outputPath.replace(/\/[^/]+$/, ""), { recursive: true })
   await copyFile(file, outputPath)
 }