Closes#567.
The sidebar already had a "vX.Y.Z available" indicator (#566 made it a
link to that release's page) but there was no way to read the actual
changelog inline or to grab a copy-paste upgrade command. This adds
the modal the issue spec'd, layered on top of the existing
updateCheckService / environmentService backend infrastructure that
already shipped.
## Backend
- `updateCheckService.fetchAvailableVersions` now returns full release
objects (tag, name, body, publishedAt, htmlUrl) instead of just
version strings — body data is what the changelog modal renders.
`checkForUpdates` extracts the version strings for its existing
consumers; no API change visible to callers.
- New `getReleasesSince(currentVersion, channel)` returns the list of
releases strictly newer than current, filtered to the user's
channel. Reuses the same 1-hour cache as `checkForUpdates` so the
modal opening doesn't trigger an extra GitHub round-trip.
- New `GET /admin/system/updates/changelog` route in `adminSystem.js`,
same auth + UPDATE_CHECK_ENABLED gating as the existing
/updates and /updates/instructions endpoints.
- 4 unit tests (axios mocked) pin: strictly-newer filtering,
channel-scoped, empty array on GitHub fetch failure, empty array
when already on latest.
## Frontend
- New `UpdateAvailableModal.tsx` — opens from the sidebar chip. Two
sections:
1. **How to upgrade** — fetches /updates/instructions for the
environment-detected copy-paste command (Docker compose / git /
standalone). Copy-to-clipboard button per step.
2. **Release notes** — fetches /updates/changelog for every
version between current and latest in the user's channel.
Latest is auto-expanded; older releases are collapsed by
default (click to expand). Each release also has a "View on
GitHub" link to the canonical release page.
- Renders release body markdown through the existing safe
MarkdownContent component (marked + DOMPurify allowlist).
- New `updateDismissal.ts` helper — single localStorage key holds the
last-dismissed version. Chip stays hidden until a STRICTLY newer
version appears, using the same compare semantics as the backend
(stable > beta, higher beta > lower beta, semantic numeric on
major.minor.patch). 9 unit tests pin the rules.
- `VersionInfo.tsx` — chip is now a button that opens the modal
instead of an external link (the #566 link-to-release behaviour is
preserved on the modal's per-release "View on GitHub" affordance).
Dismissal triggers an immediate re-render so the chip disappears
without waiting for the next route change.
No new dependencies — uses `marked` + `DOMPurify` that were already
present in the bundle for the contract block renderer.
Paul Nothaft
832f7bad45