feat: publish to MCP Registry on release (#32)

Add mcp-publisher steps to the release workflow to automatically
publish to the MCP Registry after npm publish. Uses OIDC auth
(no additional secrets needed).

Author: fbsobreira

.github/workflows/release.yml

@@ -58,3 +58,13 @@ jobs:
         run: npm publish --access public --provenance
         env:
           NODE_AUTH_TOKEN: ${{ secrets.NPM_TOKEN }}
+
+      - name: Install mcp-publisher
+        run: |
+          curl -L "https://github.com/modelcontextprotocol/registry/releases/latest/download/mcp-publisher_$(uname -s | tr '[:upper:]' '[:lower:]')_$(uname -m | sed 's/x86_64/amd64/;s/aarch64/arm64/').tar.gz" | tar xz mcp-publisher
+
+      - name: Authenticate to MCP Registry
+        run: ./mcp-publisher login github-oidc
+
+      - name: Publish to MCP Registry
+        run: ./mcp-publisher publish