Small aircraft pilot reported on short final to LRU non-towered airport noticed another aircraft taxi onto their landing runway. They announced on CTAF they were going around and at the same time the other aircraft turned off the runway and aborted their takeoff.

Narrative

I was on short final to uncontrolled airport LRU. I had been announcing my arrival on CTAF from 15 miles out; and had no responses on the CTAF frequency - no other operators in the vicinity based on lack of radio traffic.As I turned base to final for Runway 26; and announced my position for a 5th time; I noticed an Aircraft Y taxing toward my Runway 26 on Taxiway A. As I approached short final and again announced landing 26 short final; the Aircraft Y turned from Taxiway A toward Runway 26 (my chosen landing runway) and proceeded to enter the runway.Seeing this; I announced 'going around' and proceeded to go around. It was only at this point that the Aircraft Y announced 'sorry about that; was on the wrong frequency; turning away from Runway 26 and aborting departure'.I proceeded to complete the go around; flew a standard downwind-to-base-to-final and landed on Runway 26 after the go around as intended.The Aircraft Y 'apologized' on the frequency for failing to use the correct radio. The bigger concern I have is that the Aircraft Y failed to do a clearing turn to inspect the surrounding area for landing traffic. Someone on the ground heard my calls and confirmed that the Aircraft Y did not make any announcements on CTAF. And; that the Aircraft Y was a medevac flight - an experienced pilot who should have known better.There was no issue resulting from the go-around; but had I been fixated on my landing and not scanning the area on short final; there was potential for a ground collision. Luckily; this was not an issue; and my go-around kept all involved safe and made for a 'normal' flight.I am only posting this entry as another example of why; even for experienced pilots in high performance aircraft; operations at non-towered fields requires diligence and clearing turns before taking an active runway. There was no issue with the sun position to hide my approach from the pilot - it was clear the pilot simply did not look to confirm runway readiness.My hope is that this event can serve as a reminder to both 135 and 121 operators to be attentive and do clearing turns or at least clearing scans in non-towered areas; regardless of whether traffic is heard on frequency or not. A simple look out the window could have alleviated this situation - and; for the 135 and 121 operators; it pays to remember that at untowered fields; non-radio-equipped aircraft may be operating; making a clearing turn/scan mandatory to avoid any incidents such as this.Thanks for continued focus on runway incursion safety.