ci: Allow test failures on develop even for full builds [full-build]

The "Test all projects (release)" step now has continue-on-error
for develop branch, matching the behavior of incremental builds.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: CyberdyneDevelopment

.github/workflows/ci.yml

@@ -170,6 +170,7 @@ jobs:
         run: |
           Write-Output "Release build: testing all projects..."
           dotnet test --configuration ${{ env.BUILD_CONFIGURATION }} --no-build --verbosity normal
+        continue-on-error: ${{ github.ref == 'refs/heads/develop' }}
 
       # === CACHE BUILD OUTPUTS ===
       - name: Cache build outputs