feat(chart): Moon chart from D1 and transit chart for today in the natal houses (T4)

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_017eEAG8HD3mm8gsKXgk8uU8

frontend/src/hooks/use-chart-page.ts

@@ -48,6 +48,7 @@ function mergeLayer(current: ChartViewOk, incoming: ChartViewOk, layer: ChartVie
     ...(layer === "varga" ? { vedic: incoming.vedic } : {}),
     ...(layer === "chara" ? { dasha: incoming.dasha } : {}),
     ...(layer === "western" ? { western: incoming.western } : {}),
+    ...(layer === "transit" ? { transit: incoming.transit } : {}),
   };
 }