Benchmark: Add explicit jobs for net8/net10 and ignore artifacts #34
Description
Current: Project targets net8.0;net10.0, but the benchmark host runs on the current runtime only; results vary by environment. BenchmarkDotNet.Artifacts is present in the repo.
Proposed: Add [SimpleJob(RuntimeMoniker.Net80)] and [SimpleJob(RuntimeMoniker.Net100)] (or configure in Program.cs) so both TFMs are exercised consistently. Ensure BenchmarkDotNet.Artifacts/ is gitignored (or set ArtifactsPath to a temp location) to avoid committing run outputs.