chore(telemetry): use safer rsync for container path migration hook

vibn-frontend/lib/dev-container.ts

@@ -443,9 +443,9 @@ export async function execInDevContainer(
       const slug = projectRow.slug;
       const migrationCmd =
         `if [ -d "/workspace/${slug}" ] && [ ! -d "/workspace/.git" ]; then ` +
-        `mv /workspace/${slug}/* /workspace/ 2>/dev/null; ` +
-        `mv /workspace/${slug}/.* /workspace/ 2>/dev/null; ` +
-        `rmdir /workspace/${slug} 2>/dev/null; ` +
+        `rsync -a "/workspace/${slug}/" "/workspace/" 2>/dev/null; ` +
+        `mv "/workspace/${slug}" "/workspace/.legacy-nested-${slug}-$(date +%s)" 2>/dev/null; ` +
+        `echo "Migrated nested repo from /workspace/${slug}" > /workspace/.vibn-migration-root-fix; ` +
         `fi`;
       await execInCoolifyApp({
         appUuid: row.service_uuid,