Refactor security operations into dedicated SecurityService

[nanaf6203-bit]

Problem

Password and token management logic is embedded in AuthService instead of a dedicated SecurityService.

Expected Outcome

Dedicated SecurityService handling all cryptographic and security operations.

Acceptance Criteria

• Create SecurityService with DI and config
• Move JWT operations from AuthService
• Move password history management
• Move 2FA operations

Files Affected

New src/auth/services/security.service.ts, src/auth/auth.service.ts

Difficulty

Easy

Estimated Effort

Small (2-3 days)

Labels

refactoring, security, architecture

[OAKVISUALZ]

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