Metadata for Bicep snapshot functionality

**Is your feature request related to a problem? Please describe.**
I see Bicep Snapshot as a way to validate code in a way that no breaking change was compared to previous code. You can have different bicepparam files that deploy different scenarios for your modules/templates and generate different snapshots based on them. When you modify the code you will generate new snapshots to compare if any changes were made to the code that could break/modify existing deployments unintentionally. Usually when you push new version to a module/template you will do this via pull request to review the changes. When you have made some changes in the code that haven't changed the end result in the snapshot basically you will not see the snapshot file as part of the PR. Of course this could also mean that bicep snapshot command hasn't been ran. Due to that would be nice that the JSON snapshot file contains some metadata similar to what is available when you generate ARM template from Bicep file. I would like to see:

* date and time of the generated snapshot.
* Bicep cli version
* template hash?

That way even if there are no changes to predicted resources you will see that there were changes in the file for one or more of the metadata information. That will help you determine that bicep snapshot has been ran when the changes in the template/module were made.

**Describe the solution you'd like**
above.