The agent resolved the merge conflict by keeping both sides, and the code compiled into a dead branch

Two feature branches touch the same code block. On merge the agent removes the conflict markers by keeping both versions stacked: the tightened guard from one side and the added condition from the other, plus both imports and both helpers. Typecheck passes, lint passes, the exercised tests pass, and the unreachable branch plus the near-duplicate copy ship anyway. This piece explains why keeping both sides compiles when choosing should have happened, lists the four leftovers that drift later, and gives a diff-against-both-parents check and a per-hunk decision log that expose a deferred choice before merge.