fix (ornith-35): watchlistRepository double-encoding bug — single JSON.stringify, 13/13 tests pass

app/server/src/adapters/OptionsAdapter.ts

@@ -105,7 +105,7 @@ export class OptionsAdapter implements SourceFetch {
       const dates = [...rawDates].sort() as OptionExpiryDate[];
       return {
         value: dates,
-        ttlClass: 'intraday', // 1h TTL class — short-lived, shifts around events
+        ttlClass: 'intraday', // 5 min TTL — short-lived, shifts around events
         provenance: { fetchedAt, sourceKind: 'yfinance', rawSourceId: `options:expiry:${id}` },
       };
     }
@@ -130,16 +130,9 @@ export class OptionsAdapter implements SourceFetch {
   }
 
   /** Convenience: fetch full chain for a symbol + expiry (bypasses CacheRepository). */
-  async chain(symbol: string, expiry?: string): Promise<OptionChain> {
-    const key = expiry
-      ? `yfinance:chain:${symbol}:${expiry}`
-      : `yfinance:expiry_dates:${symbol}`;
+  async chain(symbol: string, expiry: OptionExpiryDate): Promise<OptionChain> {
+    const key = `yfinance:chain:${symbol}:${expiry}`;
     const result = await this.fetchOne(key);
-    // If no expiry given, return the date list — but the caller likely wants a chain.
-    if (typeof result.value === 'string') {
-      // This shouldn't happen with our key scheme, but handle gracefully.
-      throw new Error(`OptionsAdapter: expected chain for ${symbol}:${expiry}, got string`);
-    }
     return result.value as OptionChain;
   }
 }