[Feature Request]: Create admin Web UI - Download of item messages

[luispfgarces]

Is your request related to a problem you have?

The user might need to download a message of an item on a retry queue. This intents on providing the user the ability to download the message received.

Needs:

• #112
• #116

Describe the solution you'd like

Make available a control to download the item message on the Web UI. There would be a toggle to enable/disable this functionality (via source code). It would also be possible to, via source configuration, mark specific message fields to be obfuscated/masked.

Suggestion on how to enable/disable the message download feature and mask fields for a topic:

    ...
    .ForTopic("<topic-name>", opt => {
       opt.EnableMessageDownload(true)
          .MaskFields("Email", "User.Name", "CreditCard.Name");
    })
    ...

Are you able to help bring it to life and contribute with a Pull Request?

Yes

Additional context

No response