feat: show executed native plan with metrics when in debug mode

[andygrove]

Which issue does this PR close?

N/A

Rationale for this change

To help debug performance issues, I would like to see the executed DataFusion plan with native metrics.

Example output (goes to executor logs):

Comet native query plan with metrics:
 ProjectionExec: expr=[col_0@0 as col_0, count@1 as col_1], metrics=[start_timestamp{partition=0}=2024-07-31 19:33:43.785691143 UTC, end_timestamp{partition=0}=2024-07-31 19:33:43.883594710 UTC, elapsed_compute{partition=0}=551ns, output_rows{partition=0}=7]
  AggregateExec: mode=Final, gby=[col_0@0 as col_0], aggr=[count], metrics=[start_timestamp{partition=0}=2024-07-31 19:33:43.785670424 UTC, end_timestamp{partition=0}=NONE, elapsed_compute{partition=0}=5.799264ms, output_rows{partition=0}=7]
    ScanExec: schema=[col_0: Utf8, col_1: Int64], metrics=[]

What changes are included in this PR?

How are these changes tested?

[parthchandra]

lgtm

[huaxingao]

LGTM. Thanks for the PR @andygrove