fix: add "change plan" page (#86)

model it after https://web3.storage/pricing/

needs storacha/w3ui#623 to work

<img width="1241" alt="Screenshot 2024-01-31 at 2 02 22 PM"
src="https://github.com/web3-storage/console/assets/1113/a5238123-66f1-483c-8cd0-159a7ac24710">
<img width="1244" alt="Screenshot 2024-01-31 at 2 02 27 PM"
src="https://github.com/web3-storage/console/assets/1113/736185e4-782a-4f21-8e00-48d030b50cd1">

Author: Travis Vachon