Harden fee-router payout logic and collector rotation safeguards

[grantfox-oss]

Strengthen payout routing so fee distribution, collector rotation, and edge-case splits remain deterministic and cannot silently under- or over-allocate fee flows.

• Affected files: app/contract/contracts/Folder/src/fee_router.rs, app/contract/contracts/Folder/src/fee_router_test.rs, app/contract/contracts/Folder/src/fee.rs, app/contract/contracts/Folder/src/admin.rs, app/contract/contracts/Folder/src/storage.rs, app/contract/contracts/Folder/src/types.rs, app/contract/contracts/Folder/src/lib.rs, app/contract/docs/FEE_CONFIGURATION_GUIDE.md
• Acceptance criteria:
  • Fee allocation logic preserves the configured priority order without divergence between collector, platform, and arbiter paths.
  • Invalid or partially configured fee splits are rejected or handled safely instead of producing hidden drift.
  • Unit tests cover edge cases for fee ratios, collector rotation, and zero-or-negative payout values.

[akinolavictor419-sketch]

I will love to fix this issue

[GiftedGiftB]

I can get this work done in less than 24 hours.

[SanshayMaestro]

can i work on this issue please
i would closely watch for errors and ensure the server runs

[grantfox-oss]

🦊 GrantFox — @SanshayMaestro 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 #537)
2. Your PR will be reviewed by the BlockDash-Studios 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!

@SanshayMaestro's PR #552 was approved and merged by @MaryammAli.

🏆 @SanshayMaestro: You earned 35 FoxPoints for this contribution! Your current tier: Explorer (118 total points). Track your full progress on GrantFox.

👏 Great work, @SanshayMaestro! Keep contributing to BlockDash-Studios.