Implement event polling loop

[pragmaticAweds]

Repository

This issue belongs in Fundable-Protocol/Backend under indexer/.

Migrated from Fundable-Protocol/stellar_indexer#10.

Context

The indexer needs a core loop that fetches Soroban events from a cursor position and sends them to registered handlers.

Scope

• Read current cursor
• Fetch events from Soroban RPC by ledger range
• Dispatch events to handlers
• Advance cursor only after successful processing
• Add tests with mocked RPC and repositories

Out of Scope

• Unrelated package work
• Docker, CI, or deployment work unless named in scope
• Broad refactors outside the touched package

Acceptance Criteria

• Scope items are complete
• Relevant tests are added or updated
• Documentation is updated when needed
• bun run type-check passes
• bun run test passes
• bun run lint passes
• bun run indexer:type-check passes
• bun run indexer:test passes
• bun run indexer:lint passes

Dependencies

• Implement cursor repository #26
• Add Soroban RPC client wrapper #28
• [Moved to Backend] Add event handler registration interface stellar_indexer#11

Suggested Files or Packages

• indexer/common/src/poller/

[Timothy2025-20]

@Timothy2025-20 has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Hi maintainer, am a software engineer with years of experience and an enthusiast in open source projects. i will like to resolve this issue if assigned to me, Thank you

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Timothy2025-20 to this issue.

[k-deejah]

@k-deejah has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Hi Maintainer, I can work on this

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[Properprogress1]

@Properprogress1 has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Can I please work on this task ? ETA 5hrs

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[0xElyte]

@0xElyte has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

I'd love to resolve this fast

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[Ved-viraj]

@Ved-viraj has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Hi, can I be assigned this issue please? I’ve gone through the issue carefully and I’m up for the task, kindly assign me please

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

[drips-wave]

Congratulations, @Timothy2025-20! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 30, 2026.

🧑‍💻 @Timothy2025-20: 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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