feat: add storage management and utility functions

- Implement storage service for file management
- Add support for external and system storage backends
- Include utility functions for environment variables
- Add hash utilities for secure operations
- Implement validation utilities for data integrity
- Support file encryption and secure storage
- Add proper error handling and logging for storage operations

utils/valid.go

@@ -0,0 +1,22 @@
+package utils
+
+import (
+	"regexp"
+	"strings"
+)
+
+var emailRegex = regexp.MustCompile(`^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$`)
+var domainRegex = regexp.MustCompile(`^[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$`)
+
+func IsEmailValid(email string) bool {
+	return emailRegex.MatchString(email)
+}
+
+func IsDomainValid(domain string) bool {
+	return domainRegex.MatchString(domain)
+}
+
+func IsEmailDomainValid(email, domain string) bool {
+	emailDomain := strings.Split(email, "@")[1]
+	return emailRegex.MatchString(email) && emailDomain == domain
+}