fix: support metadata-stripped SafeProxy

Author: wjmelements

src/lib/IsASafe.sol

@@ -9,8 +9,8 @@ library IsASafe {
 
     function isProbablyASafe(address account) internal view {
         uint256 codesize = account.code.length;
-        // observed Safe proxy codesize range is 110 (v1.0.0) to 171 (v1.3.0)
-        require(codesize > 80 && codesize < 240, NotSafeProxy(account));
+        // observed Safe proxy codesize range is 60 (stripped v1.5.0) to 171 (v1.3.0)
+        require(codesize > 56 && codesize < 240, NotSafeProxy(account));
         address implementation = IProxy(account).masterCopy();
         // observed Safe masterCopy size is 20869 (v1.5.0) to 24421 (v1.4.1)
         require(implementation.code.length > 8000, UnusualSafeMasterCopy(account, implementation));