docs: use JSON config example instead of shell commands

MCP servers are run via host apps with JSON config, not directly in terminal

Author: SamMorrowDrums

README.md

@@ -196,11 +196,23 @@ For stdio mode, you can use OAuth 2.1 instead of a Personal Access Token. The se
 | Docker | Device flow (enter code at github.com/login/device) | Just set `GITHUB_OAUTH_CLIENT_ID` |
 | Docker with port | PKCE (browser auto-opens) | Set `GITHUB_OAUTH_CALLBACK_PORT` and bind port |
 
-**Quick start:**
-```bash
-export GITHUB_OAUTH_CLIENT_ID=your_client_id
-export GITHUB_OAUTH_CLIENT_SECRET=your_client_secret
-./github-mcp-server stdio
+**Example MCP configuration (Docker with device flow):**
+```json
+{
+  "mcpServers": {
+    "github": {
+      "command": "docker",
+      "args": ["run", "-i", "--rm",
+        "-e", "GITHUB_OAUTH_CLIENT_ID",
+        "-e", "GITHUB_OAUTH_CLIENT_SECRET",
+        "ghcr.io/github/github-mcp-server"],
+      "env": {
+        "GITHUB_OAUTH_CLIENT_ID": "your_client_id",
+        "GITHUB_OAUTH_CLIENT_SECRET": "your_client_secret"
+      }
+    }
+  }
+}
 ```
 
 See [docs/oauth-authentication.md](docs/oauth-authentication.md) for full setup instructions, including how to create a GitHub OAuth App.