message: docs: update readme for post conditions
diff: @@ -458,6 +458,12 @@ const contractFungiblePostCondition = makeContractFungiblePostCondition(
  ### Non-fungible token post condition
  +> **Warning**
  +> The post-condition codes for NFTs are currently misleading. The Stacks blockchain's post-condition processor does NOT check ownership.
  +> It checks whether or not a principal **sent** or **did not send** an NFT.
  +> Post-conditions can NOT verify anything about the recipient of an asset.
  +> If you want to verify conditions about asset recipients, you will need to use [Clarity](https://docs.stacks.co/docs/write-smart-contracts/).
  +
  ```typescript
  import {
  NonFungibleConditionCode,
  