FieldScrubPlan

The plan resource_field_scrub_plan computes (field-grain scrub spec S5): the act consumes the
same computation. Event ids, row ids and paths only. In keep mode an empty redacted_fields
means the field has nothing prior, and the act would answer 400.

{
    "clears": [
        {
            "event_type": "string",
            "path": "string"
        }
    ],
    "folded_rows": [
        "497f6eca-6276-4993-bfeb-53cbbbba6f08"
    ],
    "kept": [
        {
            "event": "1a4a8620-0119-4336-af71-a3b3e24f5ebc",
            "paths": [
                "string"
            ],
            "why": "string"
        }
    ],
    "redacted_fields": [
        {
            "event": "1a4a8620-0119-4336-af71-a3b3e24f5ebc",
            "paths": [
                "string"
            ]
        }
    ],
    "unreachable": [
        {
            "event": "1a4a8620-0119-4336-af71-a3b3e24f5ebc",
            "paths": [
                "string"
            ],
            "why": "string"
        }
    ]
}