embulk-output-jdbc and embulk use different calendars for dates before 1582

embulk-output-jdbc uses Julian calendar before 1582.
embulk uses Gregorian calendar before 1582.
As a result, for example, if embulk inputs 1000/1/1 from CSV, embulk-output-jdbc will output 999/12/26.

Start by tracing how embulk-output-jdbc converts dates received from Embulk, then compare that behavior with Embulk's calendar handling for dates before 1582. Reproduce the 1000/1/1 CSV case and define done as consistent calendar interpretation and matching output across both components.

Written by the indexing model from the issue text.