autosign metamask messages

[0xlws]

During development it gets very time consuming to wait for the metamask window and sign the identity messages after page refresh. I replaced Signer with Wallet using the private key of a hardhat development wallet.
Improves dev experience, not sure if re-asking for signing of identity is necessary in production.
Any thoughts?

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For the default private key I think you also need to add the wallet to metamask

hardhat wallet address:

0xf39Fd6e51aad88F6F4ce6aB8827279cffFb92266

[0xlws]

Hey i went through the issues to see what is fixed in this PR and i'm listing them below.
Some where already taken care of mostly i guess and i tried to improve on it.
#56 #65 #67 #79

You can test it out on the app hosted at:
xmtp-example.vercel.app/

[elisealix22]

Thank you so much for your interest in building upon our example app! Before adding new functionality, I'd recommend opening up a feature request to talk through why it should be included by default (similar to our contributing guidelines for xmtp-js). We also encourage developers to customize and maintain their own versions of the example app so that could be another option as well!

[bhavya2611]

I think this has been fixed after the latest changes, if you still see the need for the same we can reopen this PR. Closing it for now