Inside a transaction, create a temporary staging table and load these two station rows into it with COPY ... FROM STDIN, as CSV, name then zone. Keep the spaces: they are what the import has to clean.
Park Street ,1
Downtown Crossing ,1
Insert them into stations with their names trimmed. Return the new station IDs and names, then roll back so the seed is intact for the next rep.
Expected: 2 rows on a freshly seeded database, IDs 6 and 7, Park Street and Downtown Crossing with no spaces around them. After the rollback, neither station exists.