Add Blockhash library following EIP-2935

.changeset/wet-dodos-reply.md

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+---
+'openzeppelin-solidity': minor
+---
+
+`Blockhash`: Add a library that provides access to historical block hashes using EIP-2935's history storage, extending the standard 256-block limit to 8191 blocks.

contracts/utils/Blockhash.sol

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+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.24;
+
+/**
+ * @dev Library for accessing historical block hashes beyond the standard 256 block limit.
+ * Uses EIP-2935's history storage contract which maintains a ring buffer of the last
+ * 8191 block hashes in state.
+ *
+ * For blocks within the last 256 blocks, it uses the native `BLOCKHASH` opcode.
+ * For blocks between 257 and 8191 blocks ago, it queries the EIP-2935 history storage.
+ * For blocks older than 8191 or future blocks, it returns zero, matching the `BLOCKHASH` behavior.
+ *
+ * NOTE: After EIP-2935 activation, it takes 8191 blocks to completely fill the history.
+ * Before that, only block hashes since the fork block will be available.
+ */
+library Blockhash {
+    address internal constant HISTORY_STORAGE_ADDRESS = 0x0000F90827F1C53a10cb7A02335B175320002935;
+
+    /**
+     * @dev Retrieves the block hash for any historical block within the supported range.
+     *
+     * NOTE: The function gracefully handles future blocks and blocks beyond the history window
+     * by returning zero, consistent with the EVM's native `BLOCKHASH` behavior.
+     */
+    function blockHash(uint256 blockNumber) internal view returns (bytes32) {
+        uint256 current = block.number;
+        uint256 distance;
+
+        unchecked {
+            // Can only wrap around to `current + 1` given `block.number - (2**256 - 1) = block.number + 1`
+            distance = current - blockNumber;
+        }
+
+        return distance > 256 && distance <= 8191 ? _historyStorageCall(blockNumber) : blockhash(blockNumber);
+    }
+
+    /// @dev Internal function to query the EIP-2935 history storage contract.
+    function _historyStorageCall(uint256 blockNumber) private view returns (bytes32 hash) {
+        assembly ("memory-safe") {
+            // Use scratch space to allocate blockNumber
+            mstore(0, 0x20) // Store length and clear potentially dirty scratch space
+            mstore(0x20, blockNumber) // Store the blockNumber in scratch space
+
+            // In case the history storage address is not deployed, the call will succeed
+            // without returndata, so the hash will be 0 just as querying `blockhash` directly.
+            let success := staticcall(gas(), HISTORY_STORAGE_ADDRESS, 0x20, 0, 0, 0x20)
+            // In case of failure, the returndata might include the revert reason or custom error
+            if success {
+                hash := mload(0)
+            }
+        }
+    }
+}