Fix Subscriber-Aware Post Visibility and Handle Routing

[aji70]

Task: Fix Subscriber-Aware Post Visibility and Handle Routing

Overview

Creator posts routing/visibility has gaps: handle resolution may not match string handles, and subscriber checks can fail to unlock subscribers-only content. Fix so public vs subscriber visibility works correctly.

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Goals

• Resolve creator by handle string via CreatorsService.getByHandle
• Optional JWT: if fan has active subscription, include subscribers posts
• Helper: SubscriptionsService.isActiveSubscriber(fanId, creatorId)
• GET /api/v1/creators/:handle/posts works with handles like creator_one

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Deliverables

• Optional JWT guard/middleware pattern
• Updated posts controller + integration tests
• Swagger updates for optional auth

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Acceptance Criteria

• Handle-based route resolves string handles (not numeric-only)
• Unauthenticated sees only public posts
• Subscribed fan sees public + subscribers
• Unsubscribed fan never sees subscribers posts
• Invalid handle → 404
• At least 8 tests