🚧Convert namespaces to file scoped

[CalvinWilkinson]

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Description

Convert all of the namespaces in the code base from block-scoped to file-scoped namespaces.
This can easily be done with Visual Studio or Rider by using a build code transformation in the IDE.

As the conversions are made, please make sure that the using statements are all BELOW in the namespace declaration. This will ensure that the using statements all following the current analyzer setup for the project. CASL contains the using statements inside of the namespace, not outside.

Note
More info on this C# feature can be found here and here

Before Transformation Example:

namespace CASL.Exceptions
{
    using System;
}

After Transformation Example:

namespace CASL.Exceptions

using System;

Acceptance Criteria

• All namespaces converted to file-scoped

ToDo Items

• Change type labels added to this issue. Refer to the Change Type Labels section below.
• Priority label added to this issue. Refer to the Priority Type Labels section below.
• Issue linked to the correct project (if applicable).
• Issue linked to the correct milestone (if applicable).
• Draft pull request created and linked to this issue (only required with code changes).

Issue Dependencies

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Related Work

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Additional Information:

Change Type Labels

Change Type	Label
Bug Fixes	🐛bug
Breaking Changes	🧨breaking changes
New Feature	✨new feature
Workflow Changes	workflow
Code Doc Changes	🗒️documentation/code
Product Doc Changes	📝documentation/product

Priority Type Labels

Priority Type	Label
Low Priority	low priority
Medium Priority	medium priority
High Priority	high priority

Code of Conduct

• I agree to follow this project's Code of Conduct.