Testing — every change ships with tests

Kortix is sold to enterprises: the suite must be flawless, deterministic, and auditable. This is the non-negotiable testing discipline. Companion docs: TESTING.md, docs/TEST_ARCHITECTURE.md, docs/CI_CD.md, CONTRIBUTING.md. For API-route contract flows specifically, also load ke2e-tests.

THE RULE — no change without tests

Every change that touches behaviour ships with tests in the same change. New code, changed code, bug fixes, refactors — all of it. A PR that changes behaviour and adds no test is incomplete and will not pass review.