[Fix]: clippy lints for deprecated lifetimes in functions

[prajjwalkumar17]

Summary
Functions use implicit lifetimes which are deprecated. Explicit lifetimes should be added.

Type
refactor

Context
Explicit lifetimes improve clarity and are required by modern Rust conventions.

Starter tasks

1. Locate functions flagged by Clippy.
2. • If this runs fine proceed with normal cargo clippy command, and do fuzzy search for lifetime.
3. Add <'_> or named lifetimes explicitly.
   Implementation hints

• Run cargo clippy -- -W clippy::elided_lifetimes_in_paths.

Acceptance criteria

• All functions have explicit lifetimes.
• No elided_lifetimes_in_paths warnings remain.

Clippy Command

cargo clippy -- -W clippy::elided_lifetimes_in_paths

---

Contribution Guidelines:

• Fork the repository and create a new branch for your work.
• Ensure the code follows Rust best practices and coding standards.
• Run cargo clippy and cargo fmt before submitting.
• Add unit tests if functionality changes.
• Keep commits small and meaningful.

Resources:

• Rust Clippy Book
• Rust API Guidelines

Submission Process:

• Ask the maintainers for assignment of the issue, you can request for assignment by commenting on the issue itself.
• Once assigned, submit a pull request (PR).
• Maintainers will review and provide feedback, if any.
• Maintainers can unassign issues due to inactivity, read more here.
• For this issue, please submit a PR on @juspay/deicision-engine repo, and link it to the issue.

Mentor contact
@prajjwalkumar17 @Sarthak1799 @jagan-jaya @GauravRawat369

Pre-flight

• I read the Contributing Guide and setup
• I searched existing issues and PRs

Refer here for Terms and conditions for the contest.

If you have any questions or need help getting started, feel free to ask in the comments!

[Wolfy7]

If you want, you can assign the issue to me, then I will take care of it during the "hacktoberfest"

[neerajkumar-n]

@Wolfy7 I have assigned another issue, please raise the PR and get this approved.

Or seeing that you have raised the PR here, let me get this reviewed.

[Wolfy7]

Yes, already raised an MR herefore #158 (and also a few other PRs).