add security

src/main/java/com/billpaymentservice/bbps/dto/request/LoginRequest.java

@@ -0,0 +1,18 @@
+package com.billpaymentservice.bbps.dto.request;
+
+import jakarta.validation.constraints.NotBlank;
+import jakarta.validation.constraints.Pattern;
+import lombok.Data;
+import lombok.Getter;
+import lombok.Setter;
+
+@Data
+@Getter
+@Setter
+public class LoginRequest {
+
+	@NotBlank(message = "Mobile number is required")
+	@Pattern(regexp = "^[6-9]\\d{9}$", message = "Invalid mobile number. It must be 10 digits and start with 6, 7, 8, or 9.")
+	private String mobileNumber;
+
+}