Backend configuration loading and validation

[codebestia]

Write apps/backend/docs/concepts-configuration.md explaining src/config.ts and src/config/rateLimits.ts: which variables are validated at boot and cause a hard startup failure, which are read lazily at first use, and how loadEnv() relates to the lazily-constructed object-store singleton.

Acceptance criteria:

• Lists the boot-validated set and shows the failure output when one is missing
• Explains the lazy-vs-eager split and why the object store is built lazily (avoiding a circular import)
• Documents the production/development branch in lib/storage.ts that selects the real S3 client or the local-disk store
• Cross-links the environment-variable reference rather than duplicating the full table

[Aimer6022]

@Aimer6022 has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hi boss, this task aligns well with my skill set, I'd love to work on it. Assign it to me to get started as soon as possible.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Aimer6022 to this issue.

[johdanike]

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

I'd love to take this on! I will write concepts-configuration.md to break down the boot-validated versus lazily-loaded environment variables in src/config.ts. I will explicitly document how the S3/local-disk singleton avoids circular imports and cross-link the environment variable references perfectly. Structuring and documenting scalable backend configurations is standard practice for me. Let me know if I can get assigned!

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

[drips-wave]

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

🧑‍💻 @johdanike: 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.

Warning

When opening a PR, please link it to this issue to ensure it gets tracked accurately. Points are awarded when this issue is marked as completed by the maintainer.

🤠 Repo maintainers: Please keep an eye on the contributor's progress and review their work before the due date. You can manage this issue, including adjusting its complexity and points, here.

🌊 Happy Wave 🌊

[moon-code12]

@moon-code12 has applied to work on this issue as part of the Stellar Wave Program's 9th wave.

Hi codebestia I would love to work on this issue

ℹ️ Repo Maintainers: To accept this application, review their application or assign @moon-code12 to this issue.

[MaimunaY]

@MaimunaY has applied to work on this issue as part of the Stellar Wave Program's 9th wave.

Hello Maintainer, I am a SWE and I'd be glad to take on issue #556 if it's still open. I'd greatly appreciate the opportunity and look forward to delivering a clean PR without any conflicts. Thank you.

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

[josephchimebuka]

@josephchimebuka has applied to work on this issue as part of the Stellar Wave Program's 9th wave.

Hi GM, I have reviewed this issue and taken the time to understand the requirements, current implementation, and the expected outcome. Based on my analysis, I believe this is something I can successfully handle and contribute to... Kindly assign

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

[Damola09]

@Damola09 has applied to work on this issue as part of the Stellar Wave Program's 9th wave.

Can i work on this?

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Damola09 to this issue.

[drips-wave]

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

🧑‍💻 @josephchimebuka: 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.

Warning

When opening a PR, please link it to this issue to ensure it gets tracked accurately. Points are awarded when this issue is marked as completed by the maintainer.

🤠 Repo maintainers: Please keep an eye on the contributor's progress and review their work before the due date. You can manage this issue, including adjusting its complexity and points, here.

🌊 Happy Wave 🌊