Add agent-skills to awesome-ai-plugins?

Hey, Firebase Agent Skills bundles agent skills with an MCP server so coding agents can set up Firebase projects, query Firestore, and deploy hosting.

We maintain [awesome-ai-plugins](https://github.com/hashgraph-online/awesome-ai-plugins). Would you be up for adding agent-skills with a PR? You can [edit the README directly](https://github.com/hashgraph-online/awesome-ai-plugins/edit/main/README.md).

Suggested entry:

- [agent-skills](https://github.com/firebase/agent-skills) - Official Firebase plugin bundling agent skills and an MCP server to manage projects, configure backend services, query Firestore, and deploy hosting.

[Submission guidelines](https://github.com/hashgraph-online/awesome-ai-plugins/blob/main/CONTRIBUTING.md).

Read the awesome-ai-plugins CONTRIBUTING.md guidelines and inspect the README linked in the issue. Add the suggested agent-skills entry to the appropriate section, then submit a PR to awesome-ai-plugins; done means the entry appears with the provided link and description.

Written by the indexing model from the issue text.