Implement Spark-compatible CAST from timestamp to numeric types

[andygrove]

What is the problem the feature request solves?

We need to implement CAST from timestamp to numeric to match Spark's behavior.

We can break this into multiple issues if needed.

The following example is casting timestamp c to different numeric types.

scala> spark.sql("select c, cast(c as boolean), cast(c as byte), cast(c as short), cast(c as int), cast(c as long), cast(c as decimal) from t3").show
+-------------------+----+---+-----+----------+----------+----------+
|                  c|   c|  c|    c|         c|         c|         c|
+-------------------+----+---+-----+----------+----------+----------+
|2024-01-01 00:00:00|true|-16|25328|1704092400|1704092400|1704092400|
|2023-12-12 00:00:00|true|-16| 1264|1702364400|1702364400|1702364400|
+-------------------+----+---+-----+----------+----------+----------+

Describe the potential solution

No response

Additional context

No response

[andygrove]

Also, Spark returns timestamp in seconds and Comet returns timestamp in microseconds.

// input: 2023-12-31 10:00:00.0, expected: 1.7040456E9, actual: 1.7040456E15