Support for lists and dictionaries in EO3

[caitlinadams]

We are generating STAC metadata, and wish to register a number of properties as ODC metadata fields in an EO3 metadata definition. Is it possible to get support for lists and dictionaries in EO3? Including the ability to search these fields as part of a dc.find_datasets call?

Some list examples are:

"properties": {
  "sar:beam_ids": ["IW2"],
  "sar:polarizations": ["VV", "VH"],
}

Some dictionary examples are:

"properties": {
  "processing:software": {
    "isce3": "0.24.4",
    "s1Reader": "0.2.5",
    "OPERA-adt/RTC": "1.0.4",
    "sar-pipeline": "0.2.4",
    "dem-handler": "0.2.3"
  },
  "storage:schemes": {
    "aws-std": {
      "type": "aws-s3",
        "platform": "https://{bucket}.s3.{region}.amazonaws.com",
        "bucket": "deant-data-public-dev",
        "region": "ap-southeast-2",
        "requester_pays": true
        }
    }
}