better error coordination [frontend+backend]

[nagarajpandith]

• explore the whole website and test workflow of each component. as the project is big, good searching points for this would be where mutations are called, especially admin pages.
• list down the places where there is a need for better error coordination. for eg: some places might just say "failed" or "invalid" instead of the actual error which was supposed to be displayed like "image too large" or "format not supported" note that these were just examples
• work on both backend (checking and sending the right error message) and also on client side (displaying the right error message).
• know that a lot of things can be checked on client side before sending a mutation request to backend, so utilise that wherever possible.