Fix Copilot setup workflow tool ordering (#1032)

## Summary
- move Copilot environment setup steps ahead of restore/build/test so
Node.js, Docker Buildx, and dotnet-ef are available before validation
runs
- keep Node 24 aligned with the frontend engine requirement before
`dotnet build` triggers `npm ci`
- make the dotnet-ef installation step idempotent and explicitly run
under bash

## Why
The failing Copilot agent run showed the setup workflow running `dotnet
build` before `actions/setup-node`, and the Copilot setup docs state
that if a setup step fails, the remaining setup steps are skipped.
Because the web project runs `npm ci` during build and requires Node
>=22, the agent could reach its task with Node setup skipped.

## Validation
- `dotnet restore /p:AccessToNugetFeed=false`
- `dotnet build --configuration Release --no-restore
/p:AccessToNugetFeed=false`
- `dotnet test --no-build --configuration Release` *(still has the
pre-existing failures in `CaptchaService_Verify_Success` and
`KnownBreachedPassword_IsDetected`)*
- `python` YAML parse of `.github/workflows/copilot-setup-steps.yml`
- `dotnet build
/home/runner/work/EssentialCSharp.Web/EssentialCSharp.Web/EssentialCSharp.Web/EssentialCSharp.Web.csproj
--configuration Release --no-restore /p:AccessToNugetFeed=false` after
removing `EssentialCSharp.Web/node_modules`
- `parallel_validation` (Code Review + CodeQL security scan)

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: BenjaminMichaelis <22186029+BenjaminMichaelis@users.noreply.github.com>

Author: Copilot

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

@@ -28,6 +28,11 @@ jobs:
         env:
           NUGET_AUTH_TOKEN: ${{ secrets.AZURE_DEVOPS_PAT }}
 
+      - name: Set up Node.js for frontend development
+        uses: actions/setup-node@v6
+        with:
+          node-version: '24'
+
       - name: Set up dependency caching for faster builds
         uses: actions/cache@v5
         id: nuget-cache
@@ -40,6 +45,19 @@ jobs:
             ${{ runner.os }}-nuget-${{ hashFiles('**/packages.lock.json') }}
             ${{ runner.os }}-nuget-
 
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v4
+
+      - name: Install additional development tools
+        shell: bash
+        run: |
+          echo "Installing additional tools for Copilot agent environment..."
+          if dotnet tool list --global | grep -q 'dotnet-ef'; then
+            dotnet tool update --global dotnet-ef
+          else
+            dotnet tool install --global dotnet-ef
+          fi
+
       - name: Restore with dotnet
         run: dotnet restore
 
@@ -48,19 +66,3 @@ jobs:
 
       - name: Run .NET Tests
         run: dotnet test --no-build --configuration Release
-
-      - name: Set up Docker Buildx
-        uses: docker/setup-buildx-action@v4
-
-      - name: Set up Node.js for frontend development
-        uses: actions/setup-node@v6
-        with:
-          node-version: '24'
-
-      - name: Install additional development tools
-        run: |
-          # Install common development tools that Copilot agents might need
-          echo "Installing additional tools for Copilot agent environment..."
-          
-          # Install EF Core tools globally
-          dotnet tool install --global dotnet-ef