Collapse the matrix to one linear job on the amd64 :host runner: test
once, then build x86_64 natively and aarch64 by cross-compilation, then
publish both to a Forgejo release. Authenticate the upload with a real
write token (RELEASE_TOKEN, the carvers-ci bot) -- Forgejo's auto
GITHUB_TOKEN cannot upload release attachments. prerelease is a string
input, not boolean, so its value survives an API workflow_dispatch.
Forgejo-side counterpart to the GitHub release.yml (ANW-29). Driven by
workflow_dispatch (UI or API) rather than a release-published event, so a
build can be triggered for a test. Builds the release binary natively per
target, runs the test suite first, and publishes the assets to a Forgejo
release via actions/forgejo-release.
Assumed runner labels linux-amd64 / macos-arm64 must match the forge's
act_runner registration; arm64 needs a native Apple Silicon runner. Flagged
to aav -- correct if the topology differs.
