Implement UpdateClient chain components and remove depdency to ForeignClient

[soareschen]

Closes: #2780

Description

This PR implements the minimal UpdateClient components for the chain context. A new abstract UpdateClient component is implemented for the relay context make use of the chain context components. With that, we remove the methods for building UpdateClient messages from the OfaRelay trait. The end result is that the Cosmos relay context no longer depends on the ForeignClient to perform any relaying operation.

Note that this PR only implements the minimal logic for UpdateClient. It does not perform additional checks such as misbehavior detection, or validating the client state and consensus state on the counterparty chain. These logic will be implemented in follow up PRs.

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PR author checklist:

• Added changelog entry, using unclog.
• Added tests: integration (for Hermes) or unit/mock tests (for modules).
• Linked to GitHub issue.
• Updated code comments and documentation (e.g., docs/).
• Tagged one reviewer who will be the one responsible for shepherding this PR.

Reviewer checklist:

• Reviewed Files changed in the GitHub PR explorer.
• Manually tested (in case integration/unit/mock tests are absent).