Migrate webapp from v1 to v2 of "wagmi"

[bagelface]

Description 🗒️

Update the webapp to use v2 of "wagmi" and migrate all code to work with the new version. See https://wagmi.sh/react/guides/migrate-from-v1-to-v2 for migration details.

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Details 🏗️

• Update "wagmi" package version: Update the "wagmi" package to use the latest version of v2.
• Update webapp to work with the new version: Make the necessary code changes required so that the webapp continues to function as expected with the new version of "wagmi". There should be no regression in functionality.

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Acceptance Criteria ☑️

1. All of the changes described in the "Details" section above are implemented and tested.
2. Code is clear, clean, and properly documented.
3. Any UI changes are sensible and non-regressive.