Show the SealShare version and links on the admin dashboard

A quiet line under the shares card reads "SealShare 2.1.0 · Release
notes · Website · Made by noNameWEB": the release notes link goes to the
installed version's Gitea release, the others to sealshare.nonameweb.ch
and nonameweb.ch, each in a new tab. It is page chrome, not content, so
it is a footer line rather than a card.

The image has neither .git nor CHANGELOG.md, so the version is a
constant in config/app.php, bumped with each release. AppVersionTest
fails while it differs from the newest released heading in
CHANGELOG.md, so a forgotten bump stops CI before the tag's image is
built. CHANGELOG (Unreleased) notes it.

The dashboard screenshots are unchanged: the line sits below their fold.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

app/Livewire/Admin/AdminDashboard.php

@@ -77,6 +77,7 @@ class AdminDashboard extends Component
             'totalFiles' => ShareFile::query()->whereHas('share', fn ($query) => $query->whereNotNull('completed_at'))->count(),
             'usedSpace' => $shareService->getTotalUsedSpace(),
             'maxQuota' => $shareService->getMaxStorageQuota(),
+            'version' => config('app.version'),
         ]);
     }
 }