Add feature flag system (env + DB overrides)

[usmanimamu17-create]

Problem

No feature flags.

Why

Decouple deploy from release.

Outcome

FeatureFlag model + app.services.feature_flags.is_enabled(name) with Redis cache.

Acceptance

• Env overrides DB
• Per-user rollout via consistent hash

Files

• app/services/feature_flags.py (NEW)
• app/api/v1/endpoints/flags.py (NEW)
• tests/test_feature_flags.py (NEW)

[Ssoleed]

@Ssoleed has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

Hi maintainer, please let me handle this issue efficiently

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[kureyoungabare-hub]

@kureyoungabare-hub has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

I would like to work on this issue because it aligns with my experience and interest in open-source development. I have experience with JavaScript, TypeScript, React, Node.js, Git, and REST APIs, and I enjoy building clean, maintainable, and well-tested solutions. Thank you for considering my application.

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[code-0-stella]

@code-0-stella has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

Hello, I have reviewed the issue and understand what needs to be done.

I would appreciate being assigned to it.

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[Max347bot]

@Max347bot has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

Hello maintainer please I will like to work on this issue

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[drips-wave]

Congratulations, @Max347bot! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on July 30, 2026.

🧑‍💻 @Max347bot: 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

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