refactor(data): rename Krenn to Van Maanen's Star

System S-057 assigned to real star GJ 35 (Van Maanen's Star, DG white
dwarf at 13.9 ly). Renamed across all content, server code, docs,
decisions, wiki lore, and config files. 224 files updated.

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

server/src/voice/queue.rs

@@ -242,7 +242,7 @@ mod tests {
             priority,
             npc_stable_id: 1,
             zone_id: 100,
-            culture_id: "krenn".into(),
+            culture_id: "van-maanens-star".into(),
             base_text: text.into(),
             content_type: ContentType::Dialogue,
             content_index: 0,