.Net: Optional: add an HVTracker trust badge to the README

Hi Semantic Kernel maintainers,

I maintain HVTracker, an independent, open registry that scores open-source AI agents on public supply-chain signals — OSSF Scorecard, signed commits, build provenance, license clarity, maintenance, and adoption.

Semantic Kernel is already tracked, currently at HVTrust 71.6/100 (evidence grade B):
https://hvtracker.net/agents/semantic-kernel/

Would you be open to adding an optional trust badge to your README? Three projects already have — deepset's Haystack, Composio, and AIPass. The badge links to your live, externally-computed score so visitors can audit it directly:

[![HVTrust](https://hvtracker.net/badge/semantic-kernel.svg)](https://hvtracker.net/agents/semantic-kernel/)

Guide: https://hvtracker.net/badges/ · Methodology: https://hvtracker.net/methodology/

This is entirely optional and opt-in. If it's easier, I'm happy to open the one-line README PR for you to review. And if you'd prefer that we correct any of your data or stop tracking the project, just let me know here and I'll take care of it — closing this issue is a perfectly fine "no thanks," and I won't follow up.

Thanks for your work on Semantic Kernel.

Start with the repository README and the HVTracker badge and guide links in the issue. Add the provided optional badge link in an appropriate README section, then check that the Markdown renders and the badge links to the Semantic Kernel HVTrust page.