[CI][Bench] Create summary reports for benchmarking CI run results

[ianayl]

Much easier to figure out what's wrong with the benchmarking CI runs when it tells you what's wrong immediately: https://github.com/intel/llvm/actions/runs/16789472825

[ianayl]

Test runs, feel free to get an idea of what the summaries look like here:

• regression: https://github.com/intel/llvm/actions/runs/16789472825
• no regression: https://github.com/intel/llvm/actions/runs/16887540034

[sarnex]

yaml lgtm