Interchain queries support

[asalzmann]

Summary

Add support for interchain queries. Spec: cosmos/ibc#735

Problem Definition

Interchain queries (cross-chain queries) are being used by projects across the ecosystem, and the spec is being finalized. This will allow chains to query state on other chains.

Proposal

Add support for cross-chain queries

Acceptance Criteria

Relaying proven query results at specific block heights between chains.

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[adizere]

Thank you for flagging this requirement. Could you please add details about the implementation details of interchain queries?

• where should we expect to find the protobuf files
• the timeline for when this feature is expected to be implemented and integrated into a chain
  • will interchain queries be a module, bundled with ibc-go into a SDK binary?

Any demos or recipes for testing would also be appreciated!

Found this relayer-side WIP implementation: https://github.com/defund-labs/relayer

[adizere]

Hi @asalzmann can you confirm this PR #2709 is the appropriate one for your use-case?

[adizere]

Closing this issue, as it is a duplicate of #2707.