Note

Medium Risk
Touches core JDBC parameter encoding and ResultSet date/time conversion paths, so regressions could surface as subtle timezone/day-shift or precision issues across environments. Changes are well-covered with expanded unit/integration tests but affect widely used APIs.

Overview
Fixes JDBC/client-v2 handling of Date/Time/Timestamp values to be timezone-explicit and avoid day-shift/precision bugs when using Calendar or non-default zones.

DataTypeUtils adds bidirectional SQL↔java.time conversion helpers plus safe nanosecond unix-timestamp string generation (overflow-safe) and improved time/datetime formatters. JDBC PreparedStatementImpl, WriterStatementImpl, and ResultSetImpl are updated to consistently use defaultCalendar (instead of null) and these new utilities; parameter encoding now supports Duration for Time64, encodes LocalDateTime/Instant via fromUnixTimestamp64Nano(...), and validates setObject(..., targetSqlType) types instead of emitting implicit CASTs.

Client record readers (AbstractBinaryFormatReader, MapBackedRecord) now allow Time/Time64 values read as LocalDateTime to be retrieved as Duration. Tests are heavily expanded/adjusted to cover timezone round-trips and day-shift edge cases; several implicit type-cast tests are disabled as invalid behavior.

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