[C++][Parquet] Unchecked multiplication can overflow when writing Parquet

[pitrou]

Describe the bug, including details regarding any error messages, version, and platform.

In the Parquet column writer, we sometimes multiply values before writing them, for example when converting Arrow seconds timestamps to Parquet milliseconds timestamps (the Parquet format does not support seconds timestamps).

However, we don't check for multiplication overflow, which could result in invalid data being written out.

Component(s)

C++, Parquet

[pitrou]

This was originally discovered in #47655