Should I mention the target audience in the abstract of a paper?
What you are describing is called Review Article (sometimes: survey article) and a common type of publication. This keyword should suffice to find some similar papers from your field. There is also a review-articles tag on this site.

Some journals go one step further and distinguish between regular reviews for readers who want to update their knowledge on a given field and introductory reviews for readers who wish to learn about a field from scratch. The latter can have all sorts of names.

Having your review labeled review article (or similar) should suffice to clarify the nature of the article for most readers. Additionally your abstract will not contain key phrases such as we study or we find, but rather we review or we give an overview. If your paper is aimed at a specific group of newcomers (e.g., semantic segmentation from a physicist’s point of view), then it may be indeed worth mentioning them in the abstract.

Note that some journals do not accept unsolicited review articles for peer review, but ask you to discuss your plans before you start writing. If you have a special target audience, you should discuss this with the journal at this point.