v0.3.3

ci: add release + CI pipelines; ship platform binaries (v0.3.3)

The repo had no .github/workflows, so v0.3.1/v0.3.2 were tagged with zero
release assets — 'animus plugin install launchapp-dev/animus-queue-default@vX'
failed with 'no release asset matched platform' and the plugin could only be
path-installed from a local build. Port the working release pipeline from
animus-subject-default (build x86_64/aarch64 linux + darwin, cosign-sign,
publish via softprops/action-gh-release) plus the fmt/clippy/test CI. No
functional code change from v0.3.2.