add unit test coverage for UserProjectService (user-project.service.ts)

[mengw15]

Task Summary

frontend/src/app/dashboard/service/user/project/user-project.service.ts (codecov ~33%, no spec) is an HttpClient service with ~12 methods. Cover them with Vitest + HttpClientTestingModule — assert request shape + response; no backend. See frontend/TESTING.md.

Behavior to cover

• getProjectList() -> GET; emits DashboardProject[]
• retrieveWorkflowsOfProject(pid) / retrieveFilesOfProject(pid) / retrieveProject(pid) -> GET; emit their payloads
• createProject(name) -> POST; emits the new DashboardProject
• updateProjectName(pid, name) / updateProjectDescription(pid, description) -> emit Response
• deleteProject(pid) -> DELETE; emits Response
• addWorkflowToProject(pid, wid) / removeWorkflowFromProject(pid, wid) -> emit Response
• refreshFilesOfProject(pid) updates the cached list read by getProjectFiles()
• assert method / URL / body via HttpTestingController

Task Type

• Refactor / Cleanup
• DevOps / Deployment / CI
• Testing / QA
• Documentation
• Performance
• Other