Create copilot-setup-steps.yml workflow for GitHub Copilot agents

Co-authored-by: BenjaminMichaelis <22186029+BenjaminMichaelis@users.noreply.github.com>

Author: Copilot

.github/workflows/copilot-setup-steps.yml

@@ -0,0 +1,34 @@
+name: Copilot Setup Steps
+
+on:
+  workflow_call:
+  workflow_dispatch:
+
+defaults:
+  run:
+    shell: pwsh
+
+jobs:
+  copilot-setup-steps:
+    name: copilot-setup-steps
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v5
+    - name: Setup .NET
+      uses: actions/setup-dotnet@v5
+      with:
+        dotnet-version: 8.x
+    - name: Setup Dependency Caching
+      uses: actions/cache@v4
+      id: nuget-cache
+      with:
+        path: |
+          ~/.nuget/packages
+          ${{ github.workspace }}/**/obj/project.assets.json
+        key: ${{ runner.os }}-nuget-${{ hashFiles('**/packages.lock.json') }}
+        restore-keys: |
+          ${{ runner.os }}-nuget-${{ hashFiles('**/packages.lock.json') }}
+          ${{ runner.os }}-nuget-
+
+    - name: Restore dependencies
+      run: dotnet restore