In other news, page-315

I suppose it would be similar to the rapid antigen test, so depending on how pronounced or faded the result indicator is you could argue that is a measurable level detected in the sample.

Watch this describing Electrochemiluminescence from 3:00 minutes in, and so basically you would use a light sensitivity sensor to give a value of antibodies present.

However, the idea of the measuring antibodies is really only to confirm you have had an immune response so for your original question no this would not help with indicating when you need a booster because it is not measuring your actual immune response only that you have had one in the past.
Your question is still valid.

Sorry for going full circle on you.