[salawat]

That does not solve the halting problem. The halting problem is entirely framed around making a program that can specifically compute whether another arbitrary program will return.

Tests work because they are arranged by humans to verify the system under test for validity, but only for one specific system at a time.

The halting problem is basically an admission that one is unable to write a test to verify arbitrary programs on arbitrary, Turing complete hardware. You must be 10% smarter than the piece of equipment in short.

Killing something for taking too long or eating too much memory makes no substantive judgement on whether the computation at hand is ready to return or not, You (or your OS) just unilaterally made the decision that the computation wasn't worth continuing.