Tests no longer sit next to the implementation. They import the package
through ../src, the root tsconfig still type-checks them, and the
package build and declarations cover only src/.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Faarh2Ts6StJPcz2mRiHiR
