Add new page to create Policies in frontend

[daku-de]

User story

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As a user, I would like to be able to create policy, so that I can control which data can be exchanged.

Acceptance Criteria

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• There should be a page or function for user to be able to create policy.
• When a user create policy, the frontend sends a request to the backend.
• The backend should create the necessary json file and save this policy.

DoD General Criteria

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• Feature has been merged into the main branch
• Feature has been added to the documentation
• Product owner approved features
• Developers agreed to release