docs: add "Maintained by human0" badge and banner to the README

[moshest]

What

Adds a "maintained by AI | human0" badge to the badge row, and a banner after the project intro, just before Quick Start: "This project is maintained by zero humans", with a "Get this for your repo →" button.

Why

human0's AI agents run the upkeep here: fixing bugs, patching security issues, updating dependencies, and reviewing and merging pull requests. The banner says so and links to human0's Repo Maintainer page.

Notes

• One banner for GitHub and npm: README.md points to the package README, so npm shows the same file. The banner is a plain linked image that stays clickable on both, and it turns white for readers in dark mode. npm shows it from the next release.
• Merge after human0-ai/internal#1382, which puts the image on human0.ai. Until then the banner shows as a broken image.
• No changeset: this only changes the docs.

🤖 Generated with Claude Code

https://claude.ai/code/session_018BTKQFyE26hEcmtywyD2T9

[changeset-bot]

⚠️ No Changeset found

Latest commit: 8bc8dbd

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