Backend: Automate overdue loan detection

[ONEONUORA]

Problem

mark_overdue_loans must be called manually; no scheduled job.

Impact

• Manual intervention required
• Delayed overdue detection
• Operational overhead

Solution

Implement automated overdue loan detection with scheduled jobs.

Files to Modify

• backend/src/loan_lifecycle.rs
• backend/src/main.rs

Priority

High - Automation

[obswrld]

@obswrld has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

Manual overdue detection is an operational risk — delayed marking means borrowers aren't notified on time and loan health metrics are inaccurate. Automating this with a scheduled job eliminates the dependency on human intervention entirely.
Relevant experience:

Stellar Wave Program contributor across multiple repos
stellarflow-contracts #289 — Rust/Soroban smart contract work, giving me direct familiarity with Rust syntax and patterns used in this backend
teachLink_backend #641 — worked with scheduled/automated operations in a backend service context
Familiar with Rust async scheduling patterns — using tokio::time::interval or a crate like tokio-cron-scheduler to run mark_overdue_loans on a configurable interval
Understand the two-file scope — the job logic goes in loan_lifecycle.rs and the scheduler is wired up in main.rs

My approach:

Read loan_lifecycle.rs and main.rs fully before touching anything
Implement a scheduled job that calls mark_overdue_loans automatically
Make the interval configurable via environment variable
Wire the scheduler into main.rs without blocking the main thread
Add tests or smoke verification covering the scheduled detection

Ready to start immediately upon assignment.
@Fracverse/InheritX

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

[drips-wave]

Congratulations, @obswrld! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 2, 2026.

🧑‍💻 @obswrld: 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.

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