T-3: mark CI/CD pipeline complete, update spec and plan

All manual verification passed:
- Branch push: tests only, no image build
- Non-SemVer tag: tests only, no image build
- SemVer tag (0.0.1): all jobs green, 4 tags in Gitea registry

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

spec/setup-tasks.md

@@ -43,12 +43,12 @@
 **Description:** Set up a Gitea Actions CI/CD pipeline that runs on every push, ensuring code quality before deployment.
 
 **Acceptance Criteria:**
-- [ ] Gitea Actions workflow file in `.gitea/workflows/` runs on push: test, build, publish Docker image
-- [ ] Backend tests run via Maven
-- [ ] Frontend tests run via Vitest
-- [ ] Docker image is published to the Gitea container registry on the same instance
-- [ ] Pipeline fails visibly if any test fails or the build breaks
-- [ ] Docker image is only published if all tests pass and the build succeeds
+- [x] Gitea Actions workflow file in `.gitea/workflows/` runs on push: test, build, publish Docker image
+- [x] Backend tests run via Maven
+- [x] Frontend tests run via Vitest
+- [x] Docker image is published to the Gitea container registry on the same instance
+- [x] Pipeline fails visibly if any test fails or the build breaks
+- [x] Docker image is only published if all tests pass and the build succeeds
 
 **Dependencies:** T-1, T-2