Add issuer as an initialization parameter

[pavinduLakshan]

Purpose

$subject

Related Issues

• Using baseUrl as the authorization server URL breaks authentication with Asgardeo #8

Related PRs

• N/A

Checklist

• Manual test round performed and verified.
• Documentation provided.
• Unit tests provided.

Security checks

• Followed secure coding standards in http://wso2.com/technical-reports/wso2-secure-engineering-guidelines
• Ran ESLint and Prettier fixed any issues.
• Confirmed that this PR doesn't commit any keys, passwords, tokens, usernames, or other secrets

[brionmario]

Should we make this mandatory?

IMO, we can default to inferring the base part from baseUrl and let the users override the issuer endpoint as an optional thing?

const mcpAuthServer = new McpAuthServer({
  baseUrl: process.env.BASE_URL as string,
  endpoints: { -> // optional
      issuer: process.env.ISSUER as string,
  }
}