Timetable: fix course edit page missing parameter and columns

[brianp-matrix]

Summary

• course_manage_edit.php line 143 called selectClassesByCourseID() with only 1 argument, but the method requires 2 ($gibbonCourseID, $gibbonSchoolYearID), causing an ArgumentCountError
• The query in CourseGateway::selectClassesByCourseID() also only returned gibbonCourseClassID, course, and class — missing the columns needed by the DataTable: teachersTotal, studentsActive, studentsExpected, studentsTotal, name, reportable, enrolmentMin, enrolmentMax
• Updated the query to LEFT JOIN gibbonCourseClassPerson and gibbonPerson with COUNT aggregations to provide all required columns

Test plan

• Navigate to Timetable Admin > Manage Courses > Edit any course
• Verify the page loads without errors
• Verify the classes table shows teacher count, active/expected/total student counts
• Verify under/over enrolled tags appear correctly based on enrolment min/max

[SKuipers]

Hi @brianp-matrix, thanks for your PR. I can appreciate that this may have appeared to be a bug. In looking closer at the code, the line $classes = $courseClassGateway->selectClassesByCourseID($gibbonCourseID); is correct, since the courseClassGateway does have a selectClassesByCourseID($gibbonCourseID) method.

The misunderstanding seems to be that the CourseGateway has ended up with it's own method with the same name but different method signature. While this wouldn't cause a bug on the course_manage_edit.php page since the code there is correctly accessing the courseClassGateway, it could cause AI coding tools to misunderstand this and believe that there is a bug.

We will aim to remove the duplicate method from CourseGateway, which is a knock-on effect of recent refactoring efforts. Thanks!

[SKuipers]

I've pushed the commit here: 737b22e