Implement HarvestController & Routes

[Benjtalkshow]

Implement HarvestController & Routes

Title: Create harvest submission and approval endpoints

Description:
Implement HarvestController with endpoints for harvest submission, admin approval, and history retrieval.

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Endpoints

• POST /harvest (farmer only)
• GET /harvest/pending (admin only)
• POST /harvest/:id/approve (admin only)
• POST /harvest/:id/reject (admin only)
• GET /harvest/:farmId

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Acceptance Criteria

• Harvest submission with image upload is working
• Admin approval workflow is functional
• Rejection workflow is working
• History retrieval is accurate