Get User Subscription Info

curl --request GET \
  --url https://api.elevenlabs.io/v1/user/subscription

{
  "allowed_to_extend_character_limit": true,
  "can_extend_character_limit": true,
  "can_extend_voice_limit": true,
  "can_use_instant_voice_cloning": true,
  "can_use_professional_voice_cloning": true,
  "character_count": 123,
  "character_limit": 123,
  "currency": "usd",
  "has_open_invoices": true,
  "max_voice_add_edits": 123,
  "next_character_count_reset_unix": 123,
  "next_invoice": {
    "amount_due_cents": 123,
    "next_payment_attempt_unix": 123
  },
  "professional_voice_limit": 123,
  "status": "trialing",
  "tier": "<string>",
  "voice_add_edit_counter": 123,
  "voice_limit": 123
}