feat: add workflow to publish v1.x releases on tag push

.github/workflows/release-v1x.yml

@@ -0,0 +1,81 @@
+# Publish v1.x releases when a v1.* tag is pushed
+# This allows releasing from the v1.x branch without switching GitHub's default branch
+#
+# Usage:
+#   git checkout v1.x
+#   npm version patch  # bumps version and creates tag
+#   git push origin v1.x --tags
+#
+# The workflow will automatically build, test, and publish to npm.
+
+name: Publish v1.x
+
+on:
+    push:
+        tags:
+            - 'v1.*'
+
+jobs:
+    build:
+        runs-on: ubuntu-latest
+
+        steps:
+            - uses: actions/checkout@v4
+            - uses: actions/setup-node@v4
+              with:
+                  node-version: 24
+                  cache: npm
+
+            - run: npm ci
+            - run: npm run check
+            - run: npm run build
+
+    test:
+        runs-on: ubuntu-latest
+        strategy:
+            fail-fast: false
+            matrix:
+                node-version: [18, 24]
+
+        steps:
+            - uses: actions/checkout@v4
+            - uses: actions/setup-node@v4
+              with:
+                  node-version: ${{ matrix.node-version }}
+                  cache: npm
+
+            - run: npm ci
+            - run: npm test
+
+    publish:
+        runs-on: ubuntu-latest
+        needs: [build, test]
+        environment: release
+
+        permissions:
+            contents: read
+            id-token: write
+
+        steps:
+            - uses: actions/checkout@v4
+            - uses: actions/setup-node@v4
+              with:
+                  node-version: 24
+                  cache: npm
+                  registry-url: 'https://registry.npmjs.org'
+
+            - run: npm ci
+
+            - name: Determine npm tag
+              id: npm-tag
+              run: |
+                  VERSION=$(node -p "require('./package.json').version")
+                  # Use "release-X.Y" as tag for v1.x releases
+                  # This allows users to install specific minor versions:
+                  #   npm install @modelcontextprotocol/sdk@release-1.25
+                  MAJOR_MINOR=$(echo "$VERSION" | cut -d. -f1,2)
+                  echo "tag=release-${MAJOR_MINOR}" >> $GITHUB_OUTPUT
+
+            - run: npm publish --provenance --access public --tag ${{ steps.npm-tag.outputs.tag }}
+              env:
+                  NODE_AUTH_TOKEN: ${{ secrets.NPM_TOKEN }}