phase-9: domain-driven architecture complete

- Restructured server layer with 5 domains: shared, screener, portfolio, calls, finance
- Migrated 58 TypeScript files to domain-driven structure
- Updated CLAUDE.md with new architecture documentation
- Added .gitignore rules for .md files (except CLAUDE.md)
- Removed unused CatalystAnalyst import from app.ts
- Fixed lint errors: removed unused imports, fixed regex escape, added console suppressions
- Verified no sensitive data in git history
- Server code compiles cleanly with TypeScript strict mode

server/domains/shared/entities/Etf.ts

@@ -0,0 +1,29 @@
+import { Asset } from './Asset';
+import type { EtfData, EtfMetrics } from '../types/models.model';
+
+export class Etf extends Asset {
+  metrics: EtfMetrics;
+
+  constructor(data: EtfData) {
+    super(data);
+    this.metrics = {
+      expenseRatio: parseFloat(String(data.expenseRatio)) || 0,
+      totalAssets: parseFloat(String(data.totalAssets)) || 0,
+      yield: parseFloat(String(data.yield)) || 0,
+      volume: parseFloat(String(data.volume)) || 0,
+      fiveYearReturn: parseFloat(String(data.fiveYearReturn)) || 0,
+    };
+  }
+
+  getDisplayMetrics(): Record<string, string> {
+    return {
+      Ticker: this.ticker,
+      Type: 'ETF',
+      Price: this.formatCurrency(this.currentPrice),
+      'Exp Ratio%': `${this.metrics.expenseRatio.toFixed(2)}%`,
+      'Yield%': `${this.metrics.yield.toFixed(2)}%`,
+      AUM: this.formatLargeNumber(this.metrics.totalAssets),
+      '5Y Return%': `${this.metrics.fiveYearReturn.toFixed(1)}%`,
+    };
+  }
+}