chore(spec): drop the changeset — this diff releases nothing from any published package

Measured rather than assumed: `packages/spec`'s `files[]` ships `dist`,
`json-schema`, `liveness`, `prompts`, `llms.txt`, `README.md`,
`src/**/*.zod.ts`, `CHANGELOG.md`, `api-surface`, `api-surface-declarations`
and `spec-changes.json`. `scripts/` is not among them, and the four retrofitted
files live there, so no published byte moves and the changeset would have
published a version whose tarball content is unchanged.

The label route is the gate's own prescription for this shape and it is written
by the seat, not from here; `Check Changeset` reds between this push and that
write, which is the expected shape and not a regression.

Claude-Session: https://claude.ai/code/session_019srGWGCBBCBHqcDoRZpQRh
Co-authored-by: Claude <noreply@anthropic.com>

Author: claude