Release wiring for datumctl-inventory plugin (goreleaser)

[ecv]

Problem

The datumctl-inventory plugin (#41) has no release/distribution wiring. Until it does, users can only build it from source and trust it as an unmanaged plugin (datumctl plugin trust inventory). datumctl plugin install needs published release archives with a checksums.txt in goreleaser's two-column format, binary named datumctl-inventory inside each archive.

Goal

Publish datumctl-inventory release archives so it installs via:

datumctl plugin install milo-os/datumctl-inventory          # direct GitHub
datumctl plugin install inventory                           # curated index (later)

Tasks

• .goreleaser.datumctl-inventory.yaml — builds ./cmd/datumctl-inventory for linux/darwin/windows × amd64/arm64; binary datumctl-inventory; archive names datumctl-inventory_{OS}_{Arch}.{tar.gz|zip}; checksums.txt; -X main.version.
• Decouple plugin releases from the operator: use tag prefix datumctl-inventory/vX.Y.Z (goreleaser monorepo tag_prefix).
• Release workflow triggered on datumctl-inventory/v* tags.
• Guard the operator publish.yaml so plugin tags/releases don't rebuild the operator image (tags-ignore on push + if: on the release: published jobs).
• Verify archive/checksums naming matches what datumctl's GitHub-install path expects.

Follow-on (separate)

• List in datum-cloud/datumctl-plugins for datumctl plugin install inventory by short name; add the datumctl-plugin repo topic.

Follow-up to #41.

[ecv]

Moved with the plugin to datum-cloud/inventory. Release wiring (goreleaser + workflow, archives + checksums.txt) now lives there: https://github.com/datum-cloud/inventory — installable via datumctl plugin install datum-cloud/inventory. Closing as relocated.