Optimize Yahoo Finance requests: Reduced BATCH_SIZE to 5 and added 429 retry logic

lib/munger-engine.ts

@@ -11,7 +11,7 @@ const yahooFinance = new (YahooFinance as any)({
 });
 
 // Constants
-const BATCH_SIZE = 50;
+const BATCH_SIZE = 5; // Reduced from 50 to avoid 429 errors
 
 // Config for Advanced Engine
 const RISK_CONFIG = {
@@ -23,6 +23,20 @@ const RISK_CONFIG = {
     entryLimitBufferBps: 75.0
 };
 
+// Retry helper
+async function withRetry<T>(fn: () => Promise<T>, retries = 3, delay = 2000): Promise<T> {
+    try {
+        return await fn();
+    } catch (e: any) {
+        if (retries > 0 && (e.message?.includes('429') || e.message?.includes('Too Many Requests'))) {
+            console.warn(`Hit 429, retrying in ${delay}ms... (${retries} left)`);
+            await new Promise(r => setTimeout(r, delay));
+            return withRetry(fn, retries - 1, delay * 2);
+        }
+        throw e;
+    }
+}
+
 export class MungerEngine {
 
     /**
@@ -47,9 +61,9 @@ export class MungerEngine {
             // Fetch chart data
             let history;
             try {
-                history = await yahooFinance.chart(symbol, queryOptions);
+                history = await withRetry(() => yahooFinance.chart(symbol, queryOptions));
             } catch (e) {
-                console.warn(`Failed to fetch chart for ${symbol}`);
+                console.warn(`Failed to fetch chart for ${symbol}: ${(e as Error).message}`);
                 return null;
             }
 
@@ -72,7 +86,9 @@ export class MungerEngine {
             // Fetch fundamental data
             let summary;
             try {
-                summary = await yahooFinance.quoteSummary(symbol, { modules: ['financialData', 'summaryDetail', 'price'] });
+                summary = await withRetry(() => yahooFinance.quoteSummary(symbol, {
+                    modules: ['financialData', 'summaryDetail', 'price']
+                }));
             } catch (e) {
                 console.warn(`Failed to fetch summary for ${symbol}: ${(e as Error).message}`);
                 return null;