Use io path join method to join a url path for url path prefix to serve static files in production mode in windows OS cause wrong url

[gao-jing-xin]

Prerequisites

• I have written a descriptive issue title
• I have searched existing issues to ensure the bug has not already been reported

Fastify version

5.1.0

Plugin version

7.0.1

Node.js version

22.x

Operating system

Windows

Operating system version (i.e. 20.04, 11.3, 10)

win11

Description

Use io path join method to join a url path for url path prefix (@fastify\vite\mode\production.js:50) to serve static files in the production mode in windows OS.

It leads to error in prefix url path just like "\asserts" and causes assert(path[0] === '/' || path[0] === '*', 'The first character of a path should be /or*') (find-my-way\index.js:108) to throw an Exception.

It should be changed to prefix: url.resolve(config.vite.base || '/', assetsDir), (@fastify\vite\mode\production.js:50)

Link to code that reproduces the bug

No response

Expected Behavior

No response