Adjust logic selecting node

[RogerKSI]

Fixed: #XXXX

Implementation details

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[Copilot]

Pull request overview

This PR updates the relayer’s per-chain client endpoint selection strategy to avoid strictly picking the single highest-height endpoint and instead choose an endpoint that is “close enough” to the head height, biased toward faster responders. It also adds an HTTP transport idle-connection timeout for XRPL to reduce stale keep-alive reuse issues.

Changes:

• Add per-client BlockConfirmation (or equivalent) and adjust endpoint selection to first-come-first-serve within [maxHeight - BlockConfirmation, maxHeight] (or ledger equivalent).
• XRPL: introduce a custom http.Transport with shortened IdleConnTimeout for RPC calls.
• Align similar selection logic changes across EVM, Flow, ICON, Secret, Soroban, and XRPL clients.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
relayer/chains/xrpl/client.go	Adds HTTP transport idle timeout; changes endpoint selection to first-arrival within a ledger-index window.
relayer/chains/soroban/client.go	Changes Horizon endpoint selection to first-arrival within an ingested-ledger window.
relayer/chains/secret/client.go	Changes endpoint selection to first-arrival within a block-height window.
relayer/chains/icon/client.go	Changes ICON endpoint selection to first-arrival within a block-height window.
relayer/chains/flow/client.go	Changes Flow endpoint selection to first-arrival within a block-height window.
relayer/chains/evm/client.go	Changes EVM endpoint selection to first-arrival within a block-height window and ties the window size to cfg.BlockConfirmation.

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[Copilot]

Pull request overview

Copilot reviewed 6 out of 6 changed files in this pull request and generated 6 comments.

[Copilot]

Pull request overview

Copilot reviewed 9 out of 10 changed files in this pull request and generated 7 comments.

Comments suppressed due to low confidence (4)

relayer/chains/xrpl/client.go:107

• http.DefaultTransport.(*http.Transport) can panic if http.DefaultTransport has been replaced with a non-*http.Transport RoundTripper. Consider guarding the type assertion (and falling back to a new http.Transport{} or a known-good default) before calling Clone() so Connect can't crash the relayer.

			transport := http.DefaultTransport.(*http.Transport).Clone()
			transport.IdleConnTimeout = idleConnTimeout
			opts := []rpc.ConfigOpt{
				rpc.WithHTTPClient(&http.Client{Transport: transport}),
			}

README.md:281

• There is a stray standalone > line under this heading, which will render as a Markdown blockquote and looks accidental. It should likely be removed (or moved inside a fenced code block if it is meant to be a CLI prompt).

### 7. Check that the keys for the configured chains are funded
>

You can query the balance of each configured key by running:

README.md:301

• This standalone > line between prose and the fenced code block renders as a blockquote and looks accidental. Consider removing it to keep the Markdown formatting clean.

## Generate Go Protobuf Code
Falcon uses gRPC and Protocol Buffers for its internal APIs.
If you modify any `.proto` files under the `proto/` directory, regenerate the Go code by running:
> 
```sh
make proto

README.md:333

• In the migration command examples, the SQLite commands are prefixed with > inside the fenced sh block. That looks like an accidental blockquote/prompt marker and will break copy/paste—consider removing the > prefixes so the commands are valid as-is.

```sh 
# Postgres
goose -dir relayer/db/migrations/postgres postgres "postgres://user:password@localhost:5432/falcon?sslmode=disable" up

> # SQLite
> goose -dir relayer/db/migrations/sqlite sqlite "gorm.db" up

</details>

[Copilot]

Pull request overview

Copilot reviewed 10 out of 11 changed files in this pull request and generated 8 comments.