v1.4.1 Audit Report and Deployment Address (#826)

This PR adds the Audit Report conducted on the Safe Library Migration
Contracts by the Certora Team and updates the `CHANGELOG` with the
contract addresses.

CHANGELOG.md

@@ -32,13 +32,32 @@ Solidity optimizer: `disabled`
 -   `MultiSendCallOnly` at `0x9641d764fc13c8B624c04430C7356C1C7C8102e2`
 -   `CreateCall` at `0x9b35Af71d77eaf8d7e40252370304687390A1A52`
 -   `SignMessageLib` at `0xd53cd0aB83D845Ac265BE939c57F53AD838012c9`
+-   `SafeMigration` at `0x526643F69b81B008F46d95CD5ced5eC0edFFDaC6` (target Safe version: v1.4.1)
+-   `SafeToL2Migration` at `0xfF83F6335d8930cBad1c0D439A841f01888D9f69`
+-   `SafeToL2Setup` at `0xBD89A1CE4DDe368FFAB0eC35506eEcE0b1fFdc54`
 
 ### Storage reader contracts
 
 -   `SimulateTxAccessor` at `0x3d4BA2E0884aa488718476ca2FB8Efc291A46199`
 
 ## Changes
 
+### General
+
+#### New contracts
+
+Issue: [#787](https://github.com/safe-global/safe-smart-account/issues/787)
+
+`SafeMigration` contract is a generalized migration contract that will facilitate Safe migrations. The contract takes target singleton and fallback handler addresses as constructor argument.
+
+PR: [#759](https://github.com/safe-global/safe-smart-account/pull/759)
+
+`SafeToL2Setup` contract facilitates the deployment of a Safe to the same address on all networks by automatically changing the singleton to the L2 version when not on chain ID 1.
+
+PR: [#685](https://github.com/safe-global/safe-smart-account/pull/685)
+
+`SafeToL2Migration` contract facilitates updating a Safe from 1.1.1/1.3.0/1.4.1 versions to a L2 version. This is useful when replaying a Safe from a non L2 network in a L2 network.
+
 ### Bugfixes
 
 #### Remove `gasleft()` usage in `setupModules`