Refactor PaymentService methods for clarity and consistency

- Rename methods in PaymentService for improved readability: payInvoiceWithUserWallet to payWithWallet, openExternalLightningWallet to openExternalWallet, and handlePaymentWithFallback to handlePayment.
- Update related composables (useTicketPurchase, useLightningPayment) to reflect method name changes, ensuring consistent usage across the application.
- Modify RelayHub initialization process to set relay URLs before calling initialize, enhancing configuration clarity.
- Remove legacy compatibility flags in RelayHub to streamline the codebase and improve maintainability.

src/modules/market/composables/useLightningPayment.ts

@@ -22,7 +22,7 @@ export function useLightningPayment() {
   async function payInvoice(paymentRequest: string, orderId?: string): Promise<boolean> {
     try {
       // Use PaymentService with custom success message
-      const paymentResult = await paymentService.payInvoiceWithUserWallet(
+      const paymentResult = await paymentService.payWithWallet(
         paymentRequest,
         undefined, // No specific amount requirement
         {
@@ -61,14 +61,14 @@ export function useLightningPayment() {
 
   // Open external Lightning wallet (fallback) - delegate to PaymentService
   function openExternalLightningWallet(paymentRequest: string) {
-    paymentService.openExternalLightningWallet(paymentRequest)
+    paymentService.openExternalWallet(paymentRequest)
   }
 
   // Main payment handler - tries wallet first, falls back to external
   async function handlePayment(paymentRequest: string, orderId?: string): Promise<void> {
     try {
       // Use PaymentService's automatic fallback handling
-      const result = await paymentService.handlePaymentWithFallback(
+      const result = await paymentService.handlePayment(
         paymentRequest,
         undefined, // No specific amount requirement
         {