Add configurable OAuth scopes to Fast42 initialization

[Copilot]

Fast42 previously hardcoded OAuth scopes in getAccessToken, preventing scope customization at initialization time. This change adds configurable scopes on initialization and preserves the existing default behavior (public, projects).

• Scope configuration in constructor

  • Introduced a Fast42Settings object with optional scopes?: string[].
  • Added default scopes: ['public', 'projects'].
  • Kept backward compatibility with the legacy positional constructor signature.

• Token request scope composition

  • Replaced hardcoded scope=projects%20public with dynamic scope composition from settings.
  • getAccessToken now builds scope as this._scopes.join('%20').

• Documentation and usage updates

  • Updated constructor docs and examples to use the settings object.
  • Documented the new scopes field and default value.

const api = new Fast42(
  [{ client_id: process.env.FTAPI_UID!, client_secret: process.env.FTAPI_SECRET! }],
  { scopes: ['public', 'projects', 'profile'] }
);