feat: Implement transaction builder with simulation

[cypriannwokolo2-creator]

Description

Build a transaction builder that handles the full lifecycle: build → simulate → sign → submit → poll.

Requirements

• Implement transaction builder
• Add pre-flight simulation
• Add resource estimation
• Add sign and submit with retry
• Add polling until final status

Acceptance Criteria

• Transactions built with proper resource estimation
• Simulation catches errors before spending gas
• Transactions submitted with retry logic
• Polling confirms final status

Priority

High

[baling-1]

@baling-1 has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

hey maintainer kindly assign this to me

ℹ️ Repo Maintainers: To accept this application, review their application or assign @baling-1 to this issue.

[bobaivigitalpoint-ui]

@bobaivigitalpoint-ui has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hello, I'd like to pick this issue up.

I'm an experienced software engineer with a strong foundation in JavaScript/TypeScript, distributed systems, and API development. I care about code quality, test coverage, and clear communication in open source work.

I've looked into this issue closely and I'm confident in my ability to deliver a high-quality implementation here.

Please assign this issue to me, I'd be happy to contribute.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @bobaivigitalpoint-ui to this issue.

[drips-wave]

Congratulations, @bobaivigitalpoint-ui! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on August 31, 2026.

🧑‍💻 @bobaivigitalpoint-ui: Please resolve the issue such that the repo's maintainers have enough time to review your contribution before the due date. You'll earn Points for completing the issue on-time, which will make you eligible for a share of the Stellar Wave Program's reward pool.

Warning

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