Create PRs automatically updating code-gen weekly

.github/workflows/code-gen.yml

@@ -1,10 +1,15 @@
 name: Code Generation
 
-on: [pull_request]
+on:
+  pull_request:
+  workflow_dispatch:
+  schedule:
+    - cron: '0 0 * * 1' # 00:00 UTC Weekly on Mondays
 
 jobs:
   up_to_date:
     name: Ensure Generated Code Up To Date
+    if: github.event_name == 'pull_request'
     runs-on: ubuntu-latest
     steps:
       - name: Checkout .NET Client
@@ -26,7 +31,7 @@ jobs:
             ${{ runner.os }}-nuget-
 
       - name: Run Code Generator
-        run: ./build.sh codegen --branch main
+        run: ./build.sh codegen --branch main --include-high-level
 
       - name: Check For Uncommitted Changes
         shell: bash -eo pipefail {0}
@@ -40,3 +45,60 @@ jobs:
             echo "$output"
             exit 1
           fi
+
+
+  update_spec:
+    name: Update Specification and Re-generate Code
+    if: github.event_name == 'workflow_dispatch' || (github.event_name == 'schedule' && github.repository == 'opensearch-project/opensearch-net')
+    runs-on: ubuntu-latest
+    permissions:
+      contents: write
+      pull-requests: write
+    steps:
+      - name: Checkout .NET Client
+        uses: actions/checkout@v4
+
+      - name: Setup .NET SDK
+        uses: actions/setup-dotnet@v3
+        with:
+          dotnet-version: |
+            5.0.x
+            6.0.x
+
+      - name: Cache Nuget Packages
+        uses: actions/cache@v3
+        with:
+          path: ~/.nuget/packages
+          key: ${{ runner.os }}-nuget-${{ hashFiles('**/*.?sproj') }}
+          restore-keys: |
+            ${{ runner.os }}-nuget-
+
+      - name: Download Latest Spec && Run Code Generator
+        run: ./build.sh codegen --branch main --include-high-level --download
+
+      - name: Get Current Date
+        id: date
+        run: echo "date=$(date +'%Y-%m-%d')" >> $GITHUB_OUTPUT
+
+      - name: Generate GitHub App Token
+        if: github.repository == 'opensearch-project/opensearch-net'
+        id: github_app_token
+        uses: tibdex/[email protected]
+        with:
+          app_id: ${{ secrets.APP_ID }}
+          private_key: ${{ secrets.APP_PRIVATE_KEY }}
+          installation_id: 22958780
+
+      - name: Create Pull Request
+        uses: peter-evans/create-pull-request@v6
+        with:
+          token: ${{ steps.github_app_token.outputs.token || secrets.GITHUB_TOKEN }}
+          commit-message: Re-generate client code using latest OpenSearch API specification (${{ steps.date.outputs.date }})
+          title: Re-generated client code using latest OpenSearch API specification
+          body: |
+            Re-generated client code using latest OpenSearch API specification.
+            Date: ${{ steps.date.outputs.date }}
+          branch: code-gen/${{ github.ref_name }}/update
+          signoff: true
+          labels: |
+            autocut