Plan CRUD api routes needed for Days

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The issue title mentions planning CRUD API routes for 'Days', but the body is empty. Start by examining the existing codebase to understand the 'Days' model or entity, then look at similar API route definitions in the project. Determine the required endpoints (create, read, update, delete) and their specifications. Check the repository's structure for API routing patterns, possibly in directories like 'src/routes' or 'src/controllers'.

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