[FEATURE] Use configuration on the Source to determine which source attributes correspond to which Identity attributes

[drosenbauer]

The mapping function (merging_map) is used in two different ways within this connector - to populate the Identity Fusion "unique account" object with its rolled-up fields and for matching a new Source account to an Identity. So for matching, it just iterates over the Account to find the first account field in the list of field names. This could become a problem if a source has a field with a matching name, but we actually want a different one.

Since all of the authoritative source objects are available within the aggregation, we can optionally read this configuration from the Source itself. This would require that we manually add those attributes to the Source via API, but that's doable. (Or create a small CLI to do it.)

[codey-bot]

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