chore(chart): drop the qizheng palace helper left by T1

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

frontend/src/lib/chart-view-mapper.ts

@@ -610,10 +610,6 @@ function mapWestern(raw: Record<string, unknown> | null, ayanamsaDisplay: string
   };
 }
 
-function palaceBranch(row: Record<string, unknown>): string | null {
-  return text(row.branch) ?? text(row.zhi) ?? text(row.earthly_branch) ?? text(row.name);
-}
-
 export function buildChartView(bundle: ChartViewEngineBundle): ChartViewOk {
   const { chart, varga, chara, western, profile, asOf } = bundle;
   const planets = asPlanetMap(chart.planets);