Fix lint errors

[devin-ai-integration]

Fix Lint Errors

This PR fixes several lint errors identified in the GitHub Actions failure:

1. Fixed range over integer issue in engine_test.go by changing for i := range 20 { to for i := 0; i < 20; i++ {}
2. Added abi.Argument type to composite literals in userop/object.go
3. Fixed unused parameter in graphql.go by properly setting the Log field
4. Fixed unused variable in builder.go by adding the abi.Argument type to composite literals in timestampArgs

Link to Devin run

https://app.devin.ai/sessions/36c926c77b4e46a896eca1a970947902

Requested by

Chris Li (chris@avaprotocol.org)

[devin-ai-integration]

🤖 Devin AI Engineer

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[Copilot]

Pull Request Overview

This PR fixes various lint errors across the codebase. It updates loops in tests, updates composite literals for ABI arguments in user operations, and corrects the handling of the log parameter in the GraphQL client.

• Updated the test loop in engine_test.go from a range loop to an explicit index loop.
• Updated composite literals in userop/object.go and builder.go to use the abi.Argument type.
• Changed the default log function in graphql.go to the provided log function.

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
pkg/graphql/graphql.go	Replaces a no-op log function with the provided log handler
pkg/erc4337/userop/object.go	Updates composite literal to use abi.Argument for ABI args
pkg/erc4337/preset/builder.go	Updates composite literal to use abi.Argument for uint48 types
core/taskengine/engine_test.go	Converts range loop to indexed loop to fix lint error

Comments suppressed due to low confidence (1)

pkg/graphql/graphql.go:28

• Consider adding a nil-check or a fallback for the 'log' parameter inside NewClient so that if log is nil, a default no-op function is used. This helps prevent potential nil pointer dereferences at runtime.

Log:         log,