Add AbortSignal support to openSettlement, executeSettlement, and cancelSettlement

[Jagadeeshftw]

📌 Description

Similarly to anchorsApi.ts's read functions, fetchSettlements/fetchSettlement (src/lib/settlementsApi.ts) accept an optional signal, but openSettlement, executeSettlement, and cancelSettlement do not. SettlementsPanel/SettlementDetail currently have no way to cancel an in-flight mutation if the component unmounts or the user triggers another action before the first settles.

🧩 Requirements and context

• Add an optional signal?: AbortSignal parameter to openSettlement, executeSettlement, and cancelSettlement in src/lib/settlementsApi.ts, forwarded to the underlying apiRequest call.
• No change to the functions' existing required parameters or return types.
• Wiring consuming components to pass a signal is out of scope for this issue; it's about the API layer's capability.

🛠️ Suggested execution

• Update openSettlement/executeSettlement/cancelSettlement in src/lib/settlementsApi.ts to accept and forward an optional signal.
• Extend src/lib/settlementsApi.test.ts to assert the signal is forwarded to the underlying request for each function.

✅ Acceptance criteria

• All three settlement mutation functions accept an optional AbortSignal and forward it.
• Existing call sites without a signal continue to work unchanged.
• Test coverage for signal forwarding across all three functions.

🔒 Security notes

No new attack surface; enables proper cancellation of in-flight mutation requests.

📋 Guidelines

• Minimum 95% test coverage
• Clear documentation
• Timeframe: 96 hours

[Ayinkx]

Hi i would like to work on this issue

[grantfox-oss]

🦊 GrantFox — @Ayinkx has been assigned to this issue as part of the Official Campaign | FWC26 campaign!

Next steps:

1. Open a Pull Request referencing this issue (e.g., Closes #161)
2. Your PR will be reviewed by the AnchorNet-Org maintainers

Good luck! Track your progress on GrantFox.

[grantfox-oss]

🦊 GrantFox — @Ayinkx has been assigned to this issue as part of the Official Campaign | FWC26 campaign!

Next steps:

1. Open a Pull Request referencing this issue (e.g., Closes #161)
2. Your PR will be reviewed by the AnchorNet-Org maintainers

Good luck! Track your progress on GrantFox.