fix(ci): support full desktop acceptance matrices

[pallyoung]

What changed

• distinguish full Desktop releases from Runtime-only releases in acceptance planning
• run recovery scenarios against the full Shell + Runtime candidate when the Shell version advances
• persist and validate release-kind identity across Desktop and CLI promotion reports
• validate Runtime health rollback against the previous Runtime

Why

The 0.1.2 / 0.5.9 acceptance run correctly rejected Runtime-only channels because Runtime 0.5.9 requires Shell 0.1.2. The workflow still required Runtime-only scenarios even for a full Desktop release, making a valid full release impossible to promote.

Verification

• pnpm exec vitest run --config scripts/vitest.config.ts scripts/github-workflows.test.ts --environment node
• pnpm exec biome check scripts/github-workflows.test.ts
• pnpm changeset:validate
• git diff --check

Full script tests retain existing Windows-only POSIX/symlink failures; Linux GitHub CI is the merge gate.