fix: harden copilot setup tool installation

Agent-Logs-Url: https://github.com/IntelliTect/EssentialCSharp.Web/sessions/d6590875-922c-45ea-9f77-48dbe7ac66c5

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

Author: Copilot

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

@@ -32,8 +32,6 @@ jobs:
         uses: actions/setup-node@v6
         with:
           node-version: '24'
-          cache: npm
-          cache-dependency-path: EssentialCSharp.Web/package-lock.json
 
       - name: Set up dependency caching for faster builds
         uses: actions/cache@v5
@@ -53,7 +51,7 @@ jobs:
       - name: Install additional development tools
         run: |
           echo "Installing additional tools for Copilot agent environment..."
-          dotnet tool install --global dotnet-ef
+          dotnet tool update --global dotnet-ef || dotnet tool install --global dotnet-ef
 
       - name: Restore with dotnet
         run: dotnet restore