CON-3822 add unit test instructions to chaikin

subjects/chaikin/README.md

@@ -28,6 +28,14 @@ You can see how the application should work [here](https://youtu.be/PbB2eKnA2QI)
 
 > You are free to use any library to create and handle windows, rendering, keyboard and mouse events.
 
+### Unit Tests
+
+You must implement unit tests to verify your implementation of the Chaikin algorithm. Your tests should:
+
+- Verify the coordinates of the new points generated after one iteration of the algorithm (cutting the corners at 25% and 75%).
+- Verify that the number of points increases correctly per iteration (e.g., for an open curve, $N$ points should result in $2N - 2$ points in the next step).
+- Ensure the algorithm handles edge cases, such as an input list of 0, 1, or 2 points, without crashing.
+
 ### Bonus
 
 - Make it possible to clear the screen, so that the user can select new control points.

subjects/chaikin/audit/README.md

@@ -40,6 +40,18 @@
 
 ###### After you pressed `Enter` before selecting points, is it possible to place points without needing to kill the program?
 
+##### Unit Tests
+
+##### Run the command `cargo test`.
+
+###### Do all tests pass without errors?
+
+###### Is there a test that verifies the math of a single Chaikin iteration (calculating the 1/4 and 3/4 points)?
+
+###### Is there a test checking that the point count grows correctly according to the algorithm?
+
+###### Are there tests ensuring the algorithm handles empty or single-point inputs safely?
+
 ##### Bonus
 
 ###### +When you pressed `Enter` without drawing any points, was a message displayed to inform you that you forgot to draw any points?