fix(actions): show retention info on hover for expired artifacts (#38477)

The artifact info hover tooltip (#37100) only worked for live artifacts.
Hovering an expired/deleted artifact showed nothing, and even on live
artifacts the retention date was missing on real runs.

Two root causes:

1. **Expired artifacts had no tooltip.** In the run view sidebar,
expired artifacts render in a separate branch that omitted
`data-tooltip-content` entirely, so there was nothing to hover.
2. **`ExpiresUnix` was no longer sent.** The `ActionRunAttempt` refactor
(#37119) dropped `ExpiresUnix` from `fillViewRunResponseArtifacts`, so
real runs always returned `0` and the tooltip fell back to size-only.
Only the devtest mock still populated it, which masked the regression.

Artifacts without a recorded expiry (`expiresUnix <= 0`) still degrade
gracefully to a size-only tooltip. Both states can be previewed on the
`/devtest/mock/*` actions run page.

Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

web_src/js/features/repo-actions.ts

@@ -71,6 +71,7 @@ function initRepositoryActionsView() {
       artifactsTitle: el.getAttribute('data-locale-artifacts-title'),
       artifactExpired: el.getAttribute('data-locale-artifact-expired'),
       artifactExpiresAt: el.getAttribute('data-locale-artifact-expires-at'),
+      artifactExpiredAt: el.getAttribute('data-locale-artifact-expired-at'),
       confirmDeleteArtifact: el.getAttribute('data-locale-confirm-delete-artifact'),
       showTimeStamps: el.getAttribute('data-locale-show-timestamps'),
       showLogSeconds: el.getAttribute('data-locale-show-log-seconds'),