Detail in TFA looks impressive and I promise I'll do a close reading later. But..

The whole premise of the question is hilarious. They change text in an existing one-line comment and the best models in the world think, gee, maybe I'll lint everything AND run 4000 units. Maybe 5000 integration tests too, just to ensure we collide with any other work in progress. So you write the obligatory but often-ignored obvious things into agent memory or project steering markdown or periodic nudges: You must have a hypothesis when you run expensive tests, you must spot check changes first, then start with the most relevant tests only, then move outwards only as necessary to broader labels and only then suites and only then ALL suites in a widening gyre.

But like a falcon ignoring the falconer, the models want to run the everything for anything. So you sigh, you get the model to write a deterministic hook to catch the wrong invocation of the test suite, and you spend weeks refining the rules every time you hit a edge-case, and so it goes. At least you don't have to write the involved regexes by hand, and maybe one day it will be finished..