chore: add copyright notices

contracts/staking/Unpack.sol

@@ -1,3 +1,5 @@
+// (c) 2024, Ava Labs, Inc. All rights reserved.
+// See the file LICENSE for licensing terms.
 // SPDX-License-Identifier: UNLICENSED
 pragma solidity ^0.8.0;
 

contracts/staking/tests/Unpack.t.sol

@@ -1,3 +1,5 @@
+// (c) 2024, Ava Labs, Inc. All rights reserved.
+// See the file LICENSE for licensing terms.
 // SPDX-License-Identifier: UNLICENSED
 pragma solidity ^0.8.0;
 

utils/unpack/Unpack.sol.gotmpl

@@ -1,3 +1,5 @@
+// (c) 2024, Ava Labs, Inc. All rights reserved.
+// See the file LICENSE for licensing terms.
 // SPDX-License-Identifier: UNLICENSED
 pragma solidity ^{{if .UsesMCopy}}0.8.25{{else}}0.8.0{{end}};
 

utils/unpack/Unpack.t.sol.gotmpl

@@ -1,3 +1,5 @@
+// (c) 2024, Ava Labs, Inc. All rights reserved.
+// See the file LICENSE for licensing terms.
 // SPDX-License-Identifier: UNLICENSED
 pragma solidity ^{{if .UsesMCopy}}0.8.25{{else}}0.8.0{{end}};
 

utils/unpack/unpack.go

@@ -1,3 +1,6 @@
+// (c) 2024, Ava Labs, Inc. All rights reserved.
+// See the file LICENSE for licensing terms.
+//
 // Package unpack generates Solidity code to invert `abi.encodePacked()` for
 // known, unambiguous output sizes.
 package unpack

utils/unpack/unpackgen/unpackgen.go

@@ -1,3 +1,6 @@
+// (c) 2024, Ava Labs, Inc. All rights reserved.
+// See the file LICENSE for licensing terms.
+//
 // The unpackgen binary generates Solidity code to invert `abi.encodePacked()`
 // for known, unambiguous output sizes. See the [unpack] package for details.
 package main