Custom Connectors: Support custom connect data.

[johanneskares]

There are several usecases for custom connectors that need custom data before connection.

Example A: A headless E-Mail wallet (like https://magic.link)

await connectAsync({ connector: magicWallet, customData: { email, onReadyForOtpEnter: async () => { ... } })

Example B: Coinbase Wallet custom singup

As supported in this PR: #4440

await connectAsync({ connector: coinbaseWallet, customData: { onboarding: "instant" })

Custom Connectors should be able to implement

async connect({ chainId, customData } = {}) {
   // use customData
    ....
}

[tmm]

#4453