refactor(core): add Display as a supertrait of BlockHashExt and TxidExt

Adds Display as a supertrait of BlockHashExt and TxidExt to reflect that
all hash and txid types are displayable, improving ergonomics and
readability.

Author: alexanderwiederin

src/core/block.rs

@@ -146,7 +146,7 @@ use super::transaction::{TransactionRef, TxOutRef};
 /// let hash = BlockHash::from([1u8; 32]);
 /// display_hash(&hash);
 /// ```
-pub trait BlockHashExt: AsPtr<btck_BlockHash> {
+pub trait BlockHashExt: AsPtr<btck_BlockHash> + std::fmt::Display {
     /// Serializes the block hash to raw bytes.
     ///
     /// Returns the 32-byte representation of the block hash in internal byte order.

src/core/transaction.rs

@@ -651,7 +651,7 @@ impl<'a> Clone for TxOutPointRef<'a> {
 impl<'a> Copy for TxOutPointRef<'a> {}
 
 /// Common operations for transaction IDs, implemented by both owned and borrowed types.
-pub trait TxidExt: AsPtr<btck_Txid> {
+pub trait TxidExt: AsPtr<btck_Txid> + Display {
     /// Serializes the txid to raw bytes.
     fn to_bytes(&self) -> [u8; 32] {
         let mut bytes = [0u8; 32];