Fix: update wikipedia ZIM collection version numbers

collections/wikipedia.json

@@ -15,7 +15,7 @@
       "description": "Top 100,000 articles with minimal images. Great for quick lookups.",
       "size_mb": 316,
       "url": "https://download.kiwix.org/zim/wikipedia/wikipedia_en_top_mini_2026-06.zim",
-      "version": "2025-12"
+      "version": "2026-06"
     },
     {
       "id": "top-nopic",
@@ -23,7 +23,7 @@
       "description": "Top articles without images. Good balance of content and size.",
       "size_mb": 2100,
       "url": "https://download.kiwix.org/zim/wikipedia/wikipedia_en_top_nopic_2026-06.zim",
-      "version": "2025-12"
+      "version": "2026-06"
     },
     {
       "id": "all-mini",
@@ -31,7 +31,7 @@
       "description": "All 6+ million articles in condensed format.",
       "size_mb": 12000,
       "url": "https://download.kiwix.org/zim/wikipedia/wikipedia_en_all_mini_2026-06.zim",
-      "version": "2025-12"
+      "version": "2026-06"
     },
     {
       "id": "all-nopic",
@@ -39,7 +39,7 @@
       "description": "All articles without images. Comprehensive offline reference.",
       "size_mb": 48000,
       "url": "https://download.kiwix.org/zim/wikipedia/wikipedia_en_all_nopic_2026-03.zim",
-      "version": "2025-12"
+      "version": "2026-03"
     },
     {
       "id": "all-maxi",