Cloud CI never publishes its test results: cloud runners write no JUnit XML #1026

Problem

In each cloud test workflow, the "Publish test results" step finds no report file, so the test-result checks it posts on PRs are always empty. From the Cloud CI run on #1025:

Preparing 1 report as configured.
Found and parsed 0 test report files.
ℹ️ - Cloud CI 1 test results - No test results found!

Pass/fail still works: the MATLAB step itself fails when a test fails. What is lost:

• per-test results and annotations on the PR;
• any summary of incomplete tests ("Filtered by assumption").

Skipped tests are therefore visible only by reading the raw job log.

Cause

All three cloud workflows run mikepenz/action-junit-report with report_paths: 'docs/reports/test-results.xml':

• test-cloud-prod.yml
• test-cloud-api.yml
• test-cloud-api-crossplatform.yml

Their runners never write that file:

• tools/tasks/testCloudApiPart.m, called through testCloudApiProdPart, creates a TestRunner.withTextOutput and calls runner.run(...) without adding an XML plugin.
• tools/tasks/testCloudApi.m does the same.

The no-cloud suite works because tools/tasks/testToolboxNoCloud.m adds:

runner.addPlugin(XMLPlugin.producingJUnitFormat(fullfile(outputDirectory, 'test-results.xml')));

Fix

1. In testCloudApiPart.m and testCloudApi.m, before runner.run, create docs/reports/ if it doesn't exist and add matlab.unittest.plugins.XMLPlugin.producingJUnitFormat(fullfile(projectRootDir, 'docs', 'reports', 'test-results.xml')). The path should match what testToolboxNoCloud writes.
2. Once the reports are written, consider setting the action's include_passed or detailed_summary so the check also lists incomplete (assumption-filtered) tests, not just failures.