.NET AES JSON Decryptor

I need a small but robust .NET application that can pull encrypted JSON blobs straight from my database and decrypt them on the fly using the existing AES key / IV pair I will provide. The goal is to end up with clean, plain-text JSON that I can hand off to another service.

Here’s what I have in place and what I expect from you:

• The encrypted data already sits in a single table; you only need to read it, no writes required.
• Encryption is 100 % AES. You will get the key, IV, and an example record so you can verify the logic locally.
• I prefer a lean C# solution (target .NET 6 or later) with clear, commented code.
• The finished program should accept simple connection-string and key parameters—CLI flags or an appsettings.json entry are both fine—and print or serialize the decrypted output.

Deliverables
1. Complete Visual Studio solution or clean dotnet project folder.
2. Source code that:
 a) connects to the database,
 b) retrieves the encrypted column,
 c) performs AES decryption,
 d) outputs valid JSON.
3. A short README explaining build steps and any NuGet packages used.
4. Proof it works by successfully decrypting my sample record (I'll test this on my end).

If you have experience with secure key handling and best practices around AES in C#, I’d like to see that reflected in the implementation. Let me know roughly how long you think you’ll need once the key and sample data are in your hands.