#3401 feat: Allow flattening separator to be set via new flattening config Issue created by iamlorax ### Feature scope Inline mapping (stream maps, flattening, etc.) ### Description It would be beneficial to expand the flattening options to allow customization of the flattening separator. Reviewing _flattening.py, the infrastructure is already mostly there with the recent enhancements made in this feature: #3363 The current forced separator "__" limits the ability to use the

conform_name()

target method to standardize the schema. If I want my target to conform property names to only be separated by a single underscore, I would not be able to implement this due to some sources having property names with multiple underscores (ex: Salesforce often has fields like case__c). meltano/sdk