feat: integrate ZapsModule and enhance zap payment handling

- Added ZapsModule to the application, integrating it into the main app and webhooks modules.
- Introduced a new method in BTCPayService for processing payments to Lightning addresses, improving zap payout functionality.
- Updated WebhooksService to handle zap payment events, allowing for seamless integration of zap transactions.
- Enhanced UI components to display zap-related information, including zaps count and avatar stacks, improving user engagement.

These changes enhance the overall zap payment experience and ensure better integration of zap functionalities across the application.

backend/src/zaps/dto/create-zap-invoice.dto.ts

@@ -0,0 +1,13 @@
+import { IsNumber, IsString, Min } from 'class-validator';
+
+export class CreateZapInvoiceDto {
+  @IsString()
+  projectId: string;
+
+  @IsString()
+  filmmakerId: string;
+
+  @IsNumber()
+  @Min(1, { message: 'Amount must be at least 1 satoshi' })
+  amountSats: number;
+}