Add storage.rs TTL-pressure preflight returning required-extension estimate

[greatest0fallt1me]

Description

storage.rs extends TTLs but never tells callers how close keys are to archival. Add a preflight StorageTtlPressure { key, remaining_ledgers, recommended_bump } query so off-chain agents can pre-warm long-running markets before TTL expiry.

Requirements and Context

• Pure read function, no mutation
• Returns structured result; bounded result set
• Driven by current Env::ledger().sequence()
• Must be secure, tested, and documented
• Should be efficient and easy to review

Suggested Execution

1. Fork the repo and create a branch

   git checkout -b feature/storage-ttl-pressure-preflight

2. Implement changes
   • contracts/predictify-hybrid/src/storage.rs
   • contracts/predictify-hybrid/src/storage_layout_tests.rs
3. Test and commit
   • cargo test -p predictify-hybrid ttl_pressure
   • Cover edge cases
   • Include test output and notes in the PR

Example commit message

feat: add TTL pressure preflight query to storage module

Acceptance Criteria

• Query returns deterministic ordering by remaining_ledgers ascending
• No state mutation under any branch
• Recommended bump never exceeds maximum allowed extension

Guidelines

• No unwrap() in production paths
• Clear documentation and inline comments
• Timeframe: 96 hours

[ayaoba24]

@ayaoba24 has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

I’d love to handle this. Please assign

ℹ️ Repo Maintainers: To accept this application, review their application or assign @ayaoba24 to this issue.

[drips-wave]

Congratulations, @ayaoba24! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 30, 2026.

🧑‍💻 @ayaoba24: 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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