[Search] Cross Data Partition Searches
When multiple data partitions are available, it should be possible to issue a search query that returns results from multiple data partitions in one call -- the input should include IDs/names of data partitions to query as well as the actual query string. For the call on a data partition to succeed, the user must have read access to the data partition as well as data in the data partition itself. It may be the case that a target data partition has data and the requesting user has some access to the data partition but not to any data that the query retrieves. The specifics of how access to a data partition is defined are a concern of Entitlements; likely this Issue should be linked to an Epic involving Entitlements as well.