Chore: Code hygiene - warn-numeric-widen

[andy-hf-kwok]

Which issue does this PR close?

This PR aims to address the -Wnumeric-widen warning in the codebase. As the overall scope of strict-warning compliance is quite large, this change focuses on resolving this specific warning type as a first step. Future PRs will continue addressing other warning incrementally.

Partially closes #. https://github.com/apache/datafusion-comet/issues/2255

Rationale for this change

To clean up the code as per static check with the hope to resolve all warning and promote the restrict warning profile for the default CI build to uphold Scala code quality.

What changes are included in this PR?

To perform explicit type conversion instead of relying on runtime implicit cast.

How are these changes tested?

• Code can now compile with -Wnumeric-widen option on.
• CI continue to pass

[codecov-commenter]

Codecov Report

:x: Patch coverage is 94.11765% with 1 line in your changes missing coverage. Please review. :white_check_mark: Project coverage is 58.45%. Comparing base (f09f8af) to head (4fa23a7). :warning: Report is 709 commits behind head on main.

Files with missing lines	Patch %	Lines
...e/spark/sql/comet/CometBroadcastExchangeExec.scala	0.00%	1 Missing :warning:

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #2588      +/-   ##
============================================
+ Coverage     56.12%   58.45%   +2.33%     
- Complexity      976     1456     +480     
============================================
  Files           119      159      +40     
  Lines         11743    13892    +2149     
  Branches       2251     2375     +124     
============================================
+ Hits           6591     8121    +1530     
- Misses         4012     4570     +558     
- Partials       1140     1201      +61     

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[andy-hf-kwok]

@comphead @mbutrovich I have removed some explicit conversions and added a suppression instead, as it seems more appropriate. Would you mind to trigger the CI for this PR? Thx!