chore(syntax-coverage): record what the opaque-statement check cleared

The check of Snowflake statements kept as text clears 1,327 syntax
errors the parser accepted and 5 other contradicted receipts; the list
only shrinks. Those statements stay opaque, so no form becomes verified
through them. The join form whose FIRST and LAST cases Snowflake reads
as table aliases loses its approval until cases with a read-order
clause are recorded.

Author: kvlonge