fix: Resolve TypeScript build errors in config-loader and payments modules

- config-loader.ts line 238: Add type assertion for cachedMandateToken return (guaranteed non-null)
- payments.ts line 218: Fix submitTxHash parameter order (add undefined for txHashCommission)

Author: Your Name

javascript/src/config-loader.ts

@@ -235,7 +235,8 @@ export class ConfigLoader {
     const expiresDate = new Date(this.mandateExpiresAt);
     console.log(`✓ Mandate created successfully (expires: ${expiresDate.toISOString()})`);
 
-    return this.cachedMandateToken;
+    // TypeScript: cachedMandateToken is guaranteed to be set at this point
+    return this.cachedMandateToken as string;
   }
 
   /**

javascript/src/modules/payments.ts

@@ -214,8 +214,8 @@ export class PaymentsModule {
       await tx.wait();
       console.log('Transaction confirmed!');
 
-      // Submit to AgentPay
-      return await this.submitTxHash(mandate, tx.hash, chain, token);
+      // Submit to AgentPay (txHashCommission = undefined for this simple flow)
+      return await this.submitTxHash(mandate, tx.hash, undefined, chain, token);
 
     } catch (error: any) {
       throw new Error(`Failed to send transaction: ${error.message}`);