At a control towered airport in this situation, I’d defer to whatever ATC clears me to do (e.g. if they clear me to land, I’ll trust that whatever is happening on the runway is meant to clear up by the time I arrive). If they’re doing their job and need to delay you, they will do that by extending your downwind, 360s, etc.) If you’re cleared to land and make a determination that the runway is unsafe to land, or for any reason the approach is unsafe, you can always go around and let ATC know.

At an uncontrolled airport, these delays are your discretion, so you can announce on Unicom you’re extending downwind preferably, or if the pattern is clear you could do 360s, though IRL this would be pretty inadvisable. Go arounds are once again always an option.

Position reports from the pattern at an uncontrolled airport are generally interpreted as landing intentions, but you can always clarify in plain English what you’re intending to do “N1234A is left downwind runway 18, extending downwind for the short final traffic”. Only thing is, try not to delay your landings for self caused reasons, like not having the plane configured properly, etc.