Add registry maintainer onboarding documentation (#820)

Closes #512

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Co-authored-by: Claude <[email protected]>

Author: tadasant

docs/administration/maintainer-onboarding.md

@@ -0,0 +1,24 @@
+# Registry Maintainer Onboarding
+
+This guide covers onboarding new maintainers to the MCP Registry project.
+
+## Checklist
+
+When onboarding a new maintainer, complete the following steps:
+
+### 1. Access Repository (GitHub, Google Workspace)
+
+- [ ] Open a PR on the [modelcontextprotocol/access](https://github.com/modelcontextprotocol/access) repository
+
+### 2. MAINTAINERS.md
+
+- [ ] Add them to the `MAINTAINERS.md` file in [modelcontextprotocol/modelcontextprotocol](https://github.com/modelcontextprotocol/modelcontextprotocol)
+
+### 3. README.md
+
+- [ ] Add them to the "Current key maintainers" section in [README.md](../../README.md)
+
+### 4. Discord
+
+- [ ] Invite them to the MCP Discord server
+- [ ] Ask a Community Moderator or Core Maintainer to add them to the appropriate roles