W2-B-053 - `S3_SCAN_WEBHOOK_SECRET` default string doubles as the sentinel

[likableai]

Severity: Low | Area: backend/env | Evidence: src/config/env.ts:152-156
Impact: Fragile: if a deploy sets the real secret to exactly change-me-in-production, boot fails; conversely the sentinel value is only caught in production. Fix: Use a presence check (length>0) + distinct sentinel. Acceptance: Boot fails when variable is empty, passes when set to a real value.

[midexol]

@midexol has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hi maintainer I would like to work on this issue please assign

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[ajulaybeeb]

@ajulaybeeb has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

hi maintainer, i am a Full-Stack and web3 Developer, with 4+ years of experience. I have carefully read and understand the description of this issue, and i would like to take on this issue

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

[drips-wave]

Congratulations, @midexol! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on August 31, 2026.

🧑‍💻 @midexol: 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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[grantfox-oss]

🎉 This issue has been marked as completed on GrantFox!

@midexol's PR #859 was approved and merged by @Junman140.

🏆 @midexol: You earned 40 FoxPoints for this contribution! Your current tier: Builder (1,212 total points). Track your full progress on GrantFox.

👏 Great work, @midexol! Keep contributing to Pi-Defi-world.

[drips-wave]

This issue has been marked as completed by a Drips Wave moderator for @midexol as part of the Stellar Wave Program's 8th Wave 🥳

Moderator's reason: [Auto-assessed] PR #859 was merged by maintainer @Junman140 on 2026-08-26, and the changes correctly address issue #763 by separating the default fallback value from the sentinel check in src/config/env.ts.

😎 @midexol: You earned 200 Points for completing this issue! After the current Wave ends, you'll be eligible for a percentage of the Wave's reward pool based on the percentage of total points you've earned. Learn more here.

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ℹ️ Note: This issue was marked complete via moderation. Points were issued even though the GitHub issue remains open.