feat: adds metric engine to information_schema engines table

[killme2008]

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What's changed and what's your intention?

Adds metric engine to information_schema engines table.

Checklist

• I have written the necessary rustdoc comments.
• I have added the necessary unit tests and integration tests.
• This PR does not require documentation updates.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 84.97%. Comparing base (92a8e86) to head (912fa7d).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3599      +/-   ##
==========================================
- Coverage   85.35%   84.97%   -0.38%     
==========================================
  Files         931      931              
  Lines      154611   154612       +1     
==========================================
- Hits       131961   131389     -572     
- Misses      22650    23223     +573