Optional: add an HVTracker trust badge to the README

[YugantM]

Hi ADK 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.

ADK is already tracked, currently at HVTrust 70.6/100 (evidence grade B):
https://hvtracker.net/agents/google-adk-python/

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/google-adk-python.svg)](https://hvtracker.net/agents/google-adk-python/)

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 ADK.

[adk-bot]

🚨 Automated Spam Detection Alert 🚨
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Reason:

The issue is self-promotional spam asking the maintainers to add a README badge linking to a third-party website (hvtracker.net) for backlink/SEO purposes.