fix: native shuffle now reports spill metrics correctly

[andygrove]

Which issue does this PR close?

N/A

Rationale for this change

Native shuffle was not reporting spill metrics correctly. They were not appearing in the task metrics.

With this PR:

What changes are included in this PR?

How are these changes tested?

[andygrove]

This makes logging consistent with JVM shuffle

[codecov-commenter]

Codecov Report

❌ Patch coverage is 25.00000% with 3 lines in your changes missing coverage. Please review.
✅ Project coverage is 59.85%. Comparing base (f09f8af) to head (cccb6f9).
⚠️ Report is 849 commits behind head on main.

Files with missing lines	Patch %	Lines
...t/execution/shuffle/CometNativeShuffleWriter.scala	25.00%	2 Missing and 1 partial ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #3197      +/-   ##
============================================
+ Coverage     56.12%   59.85%   +3.72%     
- Complexity      976     1415     +439     
============================================
  Files           119      168      +49     
  Lines         11743    15589    +3846     
  Branches       2251     2590     +339     
============================================
+ Hits           6591     9331    +2740     
- Misses         4012     4948     +936     
- Partials       1140     1310     +170     

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[mbutrovich]

Thanks @andygrove! This is helpful for debugging production workloads!