Extract repositories to their own folder, keeping the database file in `Data`

[nanotaboada]

Description

The current project structure places both repositories and the database file under the root directory. For improved organization and clarity, we need to extract the repository-related files into their own folder while keeping the database file in the existing Data folder. This will make the project structure cleaner and more maintainable.

Suggested Approach

1. Create a new folder named Repositories in the root directory.
2. Move the following files from the root directory to the Repositories folder:
   • IPlayerRepository.cs
   • IRepository.cs
   • PlayerRepository.cs
   • Repository.cs
3. Ensure that the PlayerDbContext.cs file remains in the root or Data folder as appropriate, based on your project structure.
4. Verify that the players-sqlite3.db file stays in the Data folder.
5. Adjust namespaces and any necessary references in the code to reflect the new folder structure.
6. Run tests to ensure the functionality is not broken after the restructuring.

Acceptance Criteria

• The Repositories folder exists and contains the following files:
  • IPlayerRepository.cs
  • IRepository.cs
  • PlayerRepository.cs
  • Repository.cs
• The Data folder still contains the database file players-sqlite3.db.
• All relevant namespaces and using directives are updated accordingly.
• The application runs without errors, and all tests pass after the restructuring.