Shorten thread route from /thread to /t

All internal links (tiles, prev/next nav, comments, notifications,
breadcrumb, dropzone route check) point to /t/<id>. A global route
middleware permanently redirects old /thread/<id> URLs including
query string and comment anchor.

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Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

app/pages/user/[id].vue

@@ -313,7 +313,7 @@ const timeAgo = useTimeAgo()
             <NuxtLink
               v-for="comment in comments.items"
               :key="comment.id"
-              :to="`/thread/${comment.uploadId}#comment-${comment.id}`"
+              :to="`/t/${comment.uploadId}#comment-${comment.id}`"
               class="flex items-center gap-3 px-3 py-2.5 text-sm transition-colors hover:bg-accent"
             >
               <NuxtImg