Replace polling with SDK PollTransaction

[leighmcculloch]

What

Replace custom backoff-based transaction polling logic with the Go Stellar SDK's built-in PollTransaction method.

Why

The go-stellar-sdk is getting PollTransaction functionality in stellar/go-stellar-sdk#5876, which is a port over of the polling transaction logic in friendbot. Now that the logic has been incorporated into the SDK, that eliminates the need for that logic to live and be maintained here.

Dependent on:

• Migrate from stellar/go to stellar/go-stellar-sdk #37
• Add RPC client PollTransaction with exponential backoff go-stellar-sdk#5876

[socket-security]

Review the following changes in direct dependencies. Learn more about Socket for GitHub.

Diff	Package	Supply Chain Security	Vulnerability	Quality	Maintenance	License
	github.com/​stellar/​go-stellar-sdk@​v0.1.0 ⏵ v0.0.0-20260106225531-c77f40a164fb	+1

View full report

[Copilot]

Pull request overview

This PR modernizes the transaction polling implementation by replacing custom backoff-based polling logic with the Go Stellar SDK's built-in PollTransaction method. This change eliminates maintenance burden and leverages battle-tested SDK functionality.

Key Changes:

• Replaced custom pollTransactionStatus function with SDK's PollTransaction method
• Removed direct dependency on cenkalti/backoff/v4 package (now indirect via SDK)
• Updated to a development version of go-stellar-sdk that includes the PollTransaction method

Reviewed changes

Copilot reviewed 2 out of 3 changed files in this pull request and generated 1 comment.

File	Description
internal/rpcnetworkclient/client.go	Simplified transaction submission by replacing custom polling loop with SDK's PollTransaction method; removed backoff import and polling constants
go.mod	Updated go-stellar-sdk to development version; moved backoff package to indirect dependencies
go.sum	Updated checksums for go-stellar-sdk version change

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[leighmcculloch]

Ready for review and merging.

This PR now depends on a specific commit of go-stellar-sdk (c77f40a164fb) rather than a released version in order to use the new PollTransactionWithOptions functionality. This is fine because there's nothing incompatible on the main branch of go-stellar-sdk since the last release, and friendbot would like to use this functionality now without being blocked on a release.

[urvisavla]

lgtm!