docs: point "Who is using Rig?" to awesome-rig

[gold-silver-copper]

Description

The "Who is using Rig?" section in the root README and in crates/rig-core/README.md had grown into a per-project list that duplicated awesome-rig. This replaces it with a two-paragraph section: one sentence summarising the kinds of things people build with Rig, and a single link to awesome-rig as the place to explore and add projects.

The heading and its #who-is-using-rig anchor are unchanged, so the table of contents and the CHANGELOG reference still resolve. No images belonged to the section, so no assets were removed.

Before (root README, abbreviated):

Below is a non-exhaustive list of companies and people who are using Rig:

• St Jude - Using Rig for a chatbot utility …
• … 14 more entries …

For a curated list of Rig projects … check out awesome-rig.

Are you also using Rig? Open an issue to have your name added!

After:

Rig powers coding agents and developer tools, desktop and terminal AI assistants, retrieval-augmented generation and semantic search, agent memory systems, multi-agent and workflow orchestration frameworks, and production services ranging from genomics research and incident management to decentralised compute networks.

The full list of companies, applications, libraries, and articles lives in awesome-rig, a community-maintained list. Using Rig? Open a pull request there to add your project.

The categories in the summary are drawn from the projects actually listed in the old section and in awesome-rig (coding agents such as VT Code, assistants such as Ironclaw and Con, RAG and search such as Cairnify and deepwiki-rs, memory such as Cortex Memory, orchestration frameworks such as graph-flow and coral-rs, and production users St. Jude, ilert, and Dria).

Changelog

None

Migration

None

Testing

• All 15 entries from the old section are present in awesome-rig (Applications, Libraries, or Production Users), so nothing is lost. One URL differs: the README linked Con at nowledge-co/con, awesome-rig lists nowledge-co/con-terminal.
• https://github.com/0xPlaygrounds/awesome-rig returns 200.
• Searched the repository for the anchor and the removed project names; the only remaining references are the TOC entry (still valid) and a historical CHANGELOG line.
• No lychee or markdown-lint job exists in CI, so no link-check workflow to run.

Checklist:

• My code follows the style guidelines of this project
• I have updated READMEs and Rust docs affected by this change
• My changes generate no new warnings
• I did not edit CHANGELOG.md or MIGRATING.md (they are generated at release)

Notes

Docs-only. The rig-core README is the crates.io readme for rig-core, so the shorter section will show there on the next release.