bugfix: preserve user-attached tags across crawler upserts (0.34.1)

repo::crawler::sync_tags ran an unconditional DELETE FROM manga_tags
WHERE manga_id = $1, wiping every user attachment on every metadata
pass (including Unchanged ticks). Scope the delete to crawler-owned
rows (added_by IS NULL); user-attached tags now survive.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

frontend/package.json

@@ -1,6 +1,6 @@
 {
   "name": "mangalord-frontend",
-  "version": "0.34.0",
+  "version": "0.34.1",
   "private": true,
   "type": "module",
   "scripts": {