* ci: prevent concurrency cancellation on rapid main merges
The concurrency group used github.ref which is static for main
(refs/heads/main). When multiple PRs merged rapidly (~2 min apart),
each merge commit cancelled the previous CI run before it could finish.
Fix: use github.sha for push events to main (unique per commit) while
keeping the ref-based group for PR branches (cancels on new commits to
the same PR branch).
* refactor(#82): remove dead SkeletonList/SkeletonCard composables
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Co-authored-by: ronia <ronia@m57>
Co-authored-by: M57 <hy4ri@users.noreply.github.com>
