Add json field ops

[achrefbensaad]

PR Description

Introduced a new stage.json_field component that enables modifying JSON-formatted
log lines by updating or deleting specific fields.

• Supports update and delete operations
• Added drop_malformed flag to skip invalid JSON logs
• update creates the field if it does not exist
• Values for source are resolved exclusively from the .Extracted map
• Added documentation and usage examples, including a rename pattern using
  stage.json + stage.json_field

Which issue(s) this PR fixes

Notes to the Reviewer

PR Checklist

• CHANGELOG.md updated
• Documentation added
• Tests updated
• Config converters updated

[achrefbensaad]

@clayton-cornell I am not sure if I should update converters, can you please advise.

[kalleep]

Hey, thanks for making a pr but what I would really like to see before we consider this is a proposal and describe what you want too achieve and how it can be done, an example can be found here #4262.

This gives us (Alloy maintainers) a chance to discuss the proposal both internally and externally. Maybe there are other ways to already solve what you are trying to achieve or alternative solutions that could work better

[clayton-cornell]

I am not sure if I should update converters, can you please advise.

I'll wait on the results of the proposal/discussion that Karl asked for before diving into docs.