Get the analyst price target summary for one symbol

Returns a snapshot of published analyst price targets for one symbol: at most one row, or an empty data array when no targets are on file (unknown symbols and most ETFs). For each window (last month, last quarter, last year, all time) the row carries the number of targets published and their average, returned as a string to preserve precision. Averages are in the listing currency and no currency field is returned. A window with zero published targets returns null for its average rather than 0. publishers lists the sources contributing targets. Access is granted per account; keys without it receive 403 POLICY_DENIED.