Add feature flag state change audit log for compliance traceability

[RUKAYAT-CODER]

Overview

Feature flags (src/config/feature-flags.config.ts) can enable or disable critical security features (auth, rate limiting). There is no audit trail of who changed a flag, when, or what the previous value was. This is a compliance gap.

Specifications

Features:

• Log every feature flag state change with actor, old value, new value, and timestamp.

Tasks:

• Create a FeatureFlagAuditService that wraps flag reads/writes.
• Emit audit log entries on each flag change via AuditLogService.
• Expose an admin endpoint GET /feature-flags/audit returning the last 100 changes.
• Add unit tests verifying audit emission on flag toggle.

Impacted Files:

• src/config/feature-flags.config.ts
• New src/config/feature-flag-audit.service.ts

Acceptance Criteria

• Each flag change generates an audit entry with actor and diff.
• Admin endpoint returns the flag change history.
• Unit test verifies audit is called on toggle.

[karanjadavi]

@karanjadavi has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

can i work on this issue

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[Xaxxoo]

@Xaxxoo has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Hi, Can I take up on this issue ?

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[dot-enny]

@dot-enny has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Hi maintainer, can i work on this ? ETA - within the hour to 8 hours max.

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

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