Keeper: Optimize RPC queries using batched requests

[EDOHWARES]

Description

The keeper currently queries task details one by one, which is slow and hits RPC limits. We should batch these queries.

Requirements

• Use Soroban's batching capabilities if available, or fetch state in larger chunks.
• Measure and document the performance improvement.

[believetimothy]

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

Hello Maintainer, I can fix this issue.

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[habnark]

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

Hello can I work on this issue

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

[1sraeliteX]

@1sraeliteX has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Hello maintainer, I would like to work on this issue.

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