Kiwix integration: ZIM processor, dashboard tab, wiki.echo6.co citations

- ZIM processor: extract articles from ZIM files, feed into existing enrichment pipeline
- Dashboard: Kiwix tab with library table, ingest toggle, upload, remove
- kiwix-serve on port 8430, wiki.echo6.co behind Authentik
- Citation URLs point to wiki.echo6.co/{zimname}/{article_path}
- Dashboard shows WIKI type badge for ZIM-sourced content
- Appropedia EN (19,445 articles) fully ingested as proof of concept

lib/embedder.py

@@ -10,6 +10,7 @@ Dependencies: requests, qdrant-client
 Config: embedding, vector_db, processing.embed_workers
 """
 import json
+import re
 import os
 import time
 import traceback
@@ -290,7 +291,17 @@ def embed_single(file_hash, db, config):
                     page_timestamps = meta['page_timestamps']
             except Exception:
                 pass
-        if doc.get('path'):
+        # For ZIM articles, build wiki.echo6.co URL from meta.json
+        if source_type == 'zim' and meta.get('article_path'):
+            from urllib.parse import quote as url_quote
+            zim_name = meta.get('zim_name', '')
+            if not zim_name:
+                # Derive from zim_file: strip flavor/date suffix
+                zf = meta.get('zim_file', '')
+                zim_name = re.sub(r'_(?:maxi|mini|nopic)_[\d-]+\.zim$', '', zf)
+            article_path = url_quote(meta['article_path'], safe='/:@!$&()*+,;=-._~')
+            download_url = f'https://wiki.echo6.co/{zim_name}/{article_path}'
+        elif doc.get('path'):
             download_url = generate_download_url(
                 doc['path'], config.get('library_root', '/mnt/library')
             )