Fix Zimit: add required --name flag for warc2zim

warc2zim (called internally by zimit) requires --name for ZIM metadata.
Without it, argument validation fails with exit code 2.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

lib/scraper_runner.py

@@ -154,6 +154,7 @@ def _crawl_zimit(job, config, stop_event, db):
         docker_image,
         'zimit',
         '--seeds', url,
+        '--name', _sanitize_filename(domain),
         '--zim-lang', language,
         '--title', title,
         '--description', description[:80],