feat: disable manual order enrollment endpoint

[NawfalAhmed]

Description

• disable manual order enrollment endpoint

[Copilot]

Pull Request Overview

This PR disables the manual order enrollment endpoint by adding a waffle flag check that returns a 503 Service Unavailable response when the feature flag is active.

• Added waffle flag check to return 503 error when disable_ecommerce_service flag is active
• Added request logging for monitoring purposes
• Imported necessary dependencies (JsonResponse and waffle)

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