Move benchmark result count below matrix

[PrzemyslawKlys]

Summary

• Move the benchmark result count below the generated matrix/table instead of displaying it below the filters.
• Update the benchmark website data generator so regenerated benchmark partials keep the count at the bottom automatically.
• Keep the toolbar overlap fix intact while simplifying the count-only responsive styling.

Validation

• git diff --check
• node --check Website\static\js\benchmarks.js
• .\Website\build.ps1 -SkipBuildTool -Dev -Only build-site,verify-excel-benchmark-page
• Browser/Playwright rendered check on http://localhost:8097/benchmarks/: count is outside the toolbar, below the table wrapper, and still updates from Showing 24 of 254 rows back to Showing 254 of 254 rows after Reset.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 70.93%. Comparing base (54e7f09) to head (dfa9514).
⚠️ Report is 2 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #1874   +/-   ##
=======================================
  Coverage   70.93%   70.93%           
=======================================
  Files        1253     1253           
  Lines      185378   185378           
  Branches    39832    39832           
=======================================
+ Hits       131505   131507    +2     
+ Misses      35066    35064    -2     
  Partials    18807    18807           

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.