fix: add missing QuerySequence case to socket client resMatchesReq (backport #2844)

[mergify]

Summary

• The resMatchesReq function in the socket ABCI client (abci/client/socket_client.go) was missing a case for Request_QuerySequence ↔ Response_QuerySequence. When QuerySequence was called over the socket transport, the client treated the valid response as "unexpected", stopped itself with an error, and killTMOnClientError terminated the node process.
• This was reported via the Hacken bug bounty program as a remote DoS vector: a peer sends a SeenTx message with a non-empty Signer, the CAT reactor calls querySequenceFromApplication, which triggers the bug over the socket transport.
• Real-world impact is low because celestia-app (and Cosmos SDK apps in general) use the in-process local ABCI client, not the socket transport. The local client calls QuerySequence directly and is unaffected.
• The fix adds the missing case to resMatchesReq. A regression test (TestQuerySequenceCrashesSocketClient) is included.

Test plan

• TestQuerySequenceCrashesSocketClient — calls QuerySequence over the socket transport and verifies the client remains healthy
• Existing socket client tests still pass (go test ./abci/client/...)

🤖 Generated with Claude Code

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This is an automatic backport of pull request #2844 done by [Mergify](https://mergify.com).

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