Remove zero star rating

[Ismaillat]

Task Description:

Currently, posts that have not been rated by a user are incorrectly treated as having a rating of 0. This skews the average grading calculation, resulting in inaccurate grades. Since the grading system uses a maximum grade of 3, unrated posts should be excluded from the average calculation to ensure accuracy and fairness in the grading process.

Acceptance Criteria:

Exclusion of Unrated Posts:

• Posts that have not been rated by a user should not contribute to the average grading calculation.

Average Calculation Logic:

• The average grade should be calculated as the total sum of user ratings divided by the number of users who provided a rating.
• Example: If 3 users rated a post with scores of 3, 2, and 1 (maximum grade is 3), and 2 users did not rate the post, the average should be (3+2+1)/3 = 2.0, not (3+2+1+0+0)/5 = 1.2.

Database/Backend Updates:

• Update backend logic to handle unrated posts appropriately and calculate average grades based only on valid ratings.

Testing:

• Add unit and integration tests to verify:

  • Unrated posts do not affect the average grading calculation.
  • Correct averages are displayed for posts with varying numbers of ratings within the range of 0 to 3.
  • Posts with no ratings display the correct default message.
    Documentation:

• Update relevant documentation to reflect the new average grading logic, maximum grade enforcement (3), and any changes to the UI/UX for unrated posts.