Remove the Linux desktop build from the release pipeline. It could never
succeed in this fork: the upstream Linux reusable pulls a build-env Docker
image keyed by the building commit's SHA from the upstream element-hq
registry, where the fork's SHA does not exist, so every tagged build failed
with `manifest unknown`. Desktop releases now ship macOS and Windows only.
- Drop the linux job + its release artifacts from build-healthchat-desktop.yaml
- Bump apps/desktop/package.json to 1.1.2
- Update releasing-healthchat skill + desktop README docs
Convert build-healthchat workflow from branch-push to tag-push trigger
(healthchat-v*), add version/workspace-ref/release-notes resolution,
and create a GitHub Release on tag push. Pin healthchat-workspace to
v0.5.0-rc.4 via .healthchat-workspace-version, seed the changelog with
1.0.0, and document the runbook in the releasing-healthchat skill.
joel.poyet