Add wallet connector for Passkeys

[r4vn]

Passkeys is a product from Exodus Movement, Inc., that allows dApps to integrate an embedded wallet into their applications. The embedded wallet is based on the passkey technology and allows users to access their wallet across dApps.

We had partners reach out to us asking to provide a RainbowKit connector. As per the Contribution Guide, I am creating this feature request to open a pull request for the connector.

The connector would re-use the EIP-6963 provider of Passkeys, which is already used on desktop.

[r4vn]

@DanielSinclair is there anything missing here, or would it be fine if i put up a PR?

ps: hope you're the right person to ping about this 😅