Add Stainless CI for SDK codegen

.github/workflows/stainless.yml

@@ -0,0 +1,97 @@
+name: Stainless SDK Builds
+
+on:
+  pull_request:
+    types:
+      - opened
+      - synchronize
+      - reopened
+      - closed
+    paths:
+      - "packages/server/openapi.v3.yaml"
+      - ".github/workflows/stainless.yml"
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: true
+
+env:
+  # Configure these as GitHub Actions Variables (Settings → Secrets and variables → Actions → Variables)
+  STAINLESS_ORG: ${{ vars.STAINLESS_ORG }}
+  STAINLESS_PROJECT: ${{ vars.STAINLESS_PROJECT }}
+  OAS_PATH: packages/server/openapi.v3.yaml
+
+jobs:
+  preview:
+    if: github.event_name != 'pull_request' || github.event.action != 'closed'
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      pull-requests: write
+      id-token: write
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 2
+
+      - name: Validate Stainless configuration
+        shell: bash
+        run: |
+          set -euo pipefail
+          if [[ -z "${STAINLESS_ORG}" ]]; then
+            echo "Missing STAINLESS_ORG. Set the Actions variable STAINLESS_ORG."
+            exit 1
+          fi
+          if [[ -z "${STAINLESS_PROJECT}" ]]; then
+            echo "Missing STAINLESS_PROJECT. Set the Actions variable STAINLESS_PROJECT."
+            exit 1
+          fi
+          if [[ ! -f "${OAS_PATH}" ]]; then
+            echo "OpenAPI spec not found at ${OAS_PATH}"
+            exit 1
+          fi
+
+      - name: Run preview builds
+        uses: stainless-api/upload-openapi-spec-action/preview@v1
+        with:
+          org: ${{ env.STAINLESS_ORG }}
+          project: ${{ env.STAINLESS_PROJECT }}
+          oas_path: ${{ env.OAS_PATH }}
+
+  merge:
+    if: github.event_name == 'pull_request' && github.event.action == 'closed' && github.event.pull_request.merged == true
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      pull-requests: write
+      id-token: write
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 2
+
+      - name: Validate Stainless configuration
+        shell: bash
+        run: |
+          set -euo pipefail
+          if [[ -z "${STAINLESS_ORG}" ]]; then
+            echo "Missing STAINLESS_ORG. Set the Actions variable STAINLESS_ORG."
+            exit 1
+          fi
+          if [[ -z "${STAINLESS_PROJECT}" ]]; then
+            echo "Missing STAINLESS_PROJECT. Set the Actions variable STAINLESS_PROJECT."
+            exit 1
+          fi
+          if [[ ! -f "${OAS_PATH}" ]]; then
+            echo "OpenAPI spec not found at ${OAS_PATH}"
+            exit 1
+          fi
+
+      - name: Run merge build
+        uses: stainless-api/upload-openapi-spec-action/merge@v1
+        with:
+          org: ${{ env.STAINLESS_ORG }}
+          project: ${{ env.STAINLESS_PROJECT }}
+          oas_path: ${{ env.OAS_PATH }}