[QuestEngine] Make batch review payout logic match single review

[Kaylahray]

Description

The batch approval flow should execute the same payout rules as single submission review, including platform fees, staking multiplier handling, pause checks, and consistent status transitions.

User Story

As an Employer,
I want to batch approve submissions with the exact same payout logic as single approval,
so that bulk approvals do not behave differently from individual approvals.

Requirements and Context

• Files: contracts/quest-engine/src/lib.rs, contracts/quest-engine/src/test.rs
• Refactor batch_review_submissions so each learner path reuses the same core approval logic as review_submission
• Apply the same fee transfer and staking multiplier logic used by the single-review path
• Keep batch event emission while avoiding drift between the two approval paths
• Ensure submission status and auth checks remain identical for batch and single review

Suggested Implementation

// 1. Extract the common approval flow into an internal helper.
// 2. Call the helper from review_submission.
// 3. Reuse the helper inside batch_review_submissions for each learner.
// 4. Keep BatchReviewed as the aggregate event after all learner approvals succeed.

Acceptance Criteria

• Batch approval applies the same fee and multiplier behavior as single approval.
• A change to single-review payout rules does not require duplicating the logic in a second place.
• Batch review tests cover mixed multiplier tiers and failure cases.

Submission Guidelines

• Branch: feat/batch-review-parity
• Depends on: [QuestEngine] Deliver uncapped staking multiplier payouts
• PR: refactor(quest-engine): unify batch and single review payout logic

[syed-ghufran-hassan]

Refactored batch_review_submissions to call the same process_submission_approval helper as review_submission, ensuring consistent fee/multiplier handling and adding 10 passing tests. Please assign the issue to me

[Muhammadjazuli]

I’d like to work on this. The main thing I’d focus on is removing the duplicated payout logic so batch review can’t drift from review_submission over time.

I’ll extract the shared approval path, use it from both flows, and keep the batch-specific event handling intact. I’ll also add tests around different staking multipliers and failure cases to make sure both paths behave the same.

[grantfox-oss]

🦊 GrantFox — @Muhammadjazuli has been assigned to this issue as part of the Third Campaign campaign!

Next steps:

1. Open a Pull Request referencing this issue (e.g., Closes #88)
2. Your PR will be reviewed by the learnault maintainers

Good luck! Track your progress on GrantFox.

[grantfox-oss]

🎉 This issue has been marked as completed on GrantFox as part of the Third Campaign campaign!

@Muhammadjazuli's PR #110 was approved and merged by @3m1n3nc3.

🏆 @Muhammadjazuli: You earned 35 FoxPoints for this contribution! Your current tier: Explorer (570 total points). Track your full progress on GrantFox.

👏 Great work, @Muhammadjazuli! Keep contributing to learnault.