Returned Addresses are not checksummed by default

[nalinbhardwaj]

It seems addresses returned by viem, for example by the Log type in getLogs are not checksummed by default. This can be annoying as one might expect all objects of type Address to be checksummed/consistent and for example using them as a map key would resolve to different entries (if there are addresses user may have put in manually or from https://wagmi.sh which by default does use checksummed addresses).

Two possible suggested fixes:

1. Make a checksummed Address type and use it where relevant?
2. By default return checksummed addresses everywhere from viem.