Husky initialization fails with TypeError in bun environment

[NazCodeland]

Issue Type: Bug

Troubleshoot Checklist:

• I have checked the Husky Troubleshoot Guide

Context:

• Terminal: PowerShell 7.4.2
• Node.js version: v18.19.0
• Package Manager: bun
• Husky version: 9.0.11

Description:
When trying to initialize Husky in a new project using bun as the package manager, I encounter a TypeError. The error message suggests that the npm_config_user_agent environment variable is undefined, and the script is trying to call the split method on it.

Steps to Reproduce:

1. Create a new project directory
2. Initialize git with git init
3. Install husky with bun add --dev husky
4. Try to initialize husky with bunx husky init

Expected Result:
Husky initializes successfully and creates the necessary hooks.

Actual Result:
Initialization fails with the following error:

Additional Context:
This issue occurs even in a fresh project following the steps provided in the Husky Get Started Guide.