Node.js HTTP Proxy Agents Monorepo Files

Minor Changes

• 84e85ed: Add onProxyAuth callback and negotiate option for Kerberos/SPNEGO proxy authentication

• Extract shared Negotiate/SPNEGO auth logic into new proxy-agent-negotiate package

• Added optional onProxyAuth async callback to HttpsProxyAgent and HttpProxyAgent options
• When the proxy responds with 407 Proxy-Authentication Required, the callback is invoked with the response and auth scheme
• The callback returns headers (e.g. Proxy-Authorization) to retry the request with
• Added negotiate: true option that uses the kerberos package for automatic Negotiate/SPNEGO auth
• Added kerberos as an optional peer dependency of proxy-agent-negotiate
• Extended the proxy test package to support authenticate: 'negotiate' mode for mock testing