Behaviour for adding custom claims to JWT access tokens.

Implement this behaviour to embed application-specific data in JWTs. Called during token generation after standard claims are built.

Example

defmodule MyApp.JWTClaimsBuilder do
  @behaviour Sigra.JWT.ClaimsBuilder

  @impl true
  def extra_claims(user) do
    %{"role" => user.role, "org_id" => user.org_id}
  end
end