feat: add BlockConditional (#1846)

* feat: add BlockConditional

* chore: restructure

crates/consensus/src/conditional.rs

@@ -0,0 +1,13 @@
+//! Helpers for conditional transactions.
+
+/// Contains attributes of a block that are relevant for block conditional transactions.
+///
+/// These attributes are used to determine preconditions for inclusion in the block with the given
+/// attributes (EIP-4337 transactions)
+#[derive(Debug, Clone, Copy, Default, Eq, PartialEq)]
+pub struct BlockConditionalAttributes {
+    /// The number of the block.
+    pub number: u64,
+    /// The block's timestamp
+    pub timestamp: u64,
+}

crates/consensus/src/lib.rs

@@ -26,6 +26,7 @@ pub use receipt::{
     RlpDecodableReceipt, RlpEncodableReceipt, TxReceipt,
 };
 
+pub mod conditional;
 pub mod proofs;
 
 pub mod transaction;