Graph views now correctly display results when users group data by more than two fields, including bar and line charts. This makes reports more flexible and reliable for teams analyzing data across several dimensions.

Description of the issue/feature this PR addresses:
Task ID: https://www.odoo.com/web?#id=1917948&action=333&active_id=131&model=project.task&view_type=form&menu_id=4720

Current behavior before PR:

Desired behavior after PR is merged:




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Course completion status is now calculated and shown more reliably in eLearning pages, including clearer completed badges on course listings. The update also improves course images, homepage presentation, demo content, and related course statistics so learners and administrators see more accurate information.

This update corrects how reviews, ratings, and comments are shown on website learning content. It prevents system messages from appearing as reviews, fixes duplicated star ratings, and ensures likes and simple comments are only available where appropriate.

https://www.odoo.com/web?debug#id=1941250&action=333&active_id=965&model=project.task&view_type=form&menu_id=4720