Refactor Notification Management and Enhance Customer Features

- Updated the notification handling logic to utilize a new SDK for sending notifications, improving the flexibility and scalability of the notification system.
- Introduced new methods in the notification service for sending notifications to users and customers based on various target audience types, enhancing the notification delivery capabilities.
- Added a new endpoint to assign companies to a customer, improving customer management functionalities.
- Refactored the customer entity and forms to replace 'CompanyIDs' with 'Companies', ensuring consistency across the data model.
- Enhanced API documentation with Swagger comments for the new endpoint and updated notification structures, ensuring clarity for API consumers.

internal/user/form.go

@@ -85,20 +85,21 @@ type UpdateUserRoleForm struct {
 
 // Response DTOs
 type UserResponse struct {
-	ID           string  `json:"id"`
-	FullName     string  `json:"full_name"`
-	Username     string  `json:"username"`
-	Email        string  `json:"email"`
-	Role         string  `json:"role"`
-	Status       string  `json:"status"`
-	Department   *string `json:"department"`
-	Position     *string `json:"position"`
-	Phone        *string `json:"phone"`
-	ProfileImage *string `json:"profile_image"`
-	IsVerified   bool    `json:"is_verified"`
-	LastLoginAt  *int64  `json:"last_login_at"`
-	UpdatedAt    int64   `json:"updated_at"`
-	CreatedAt    int64   `json:"created_at"`
+	ID           string   `json:"id"`
+	FullName     string   `json:"full_name"`
+	Username     string   `json:"username"`
+	Email        string   `json:"email"`
+	Role         string   `json:"role"`
+	Status       string   `json:"status"`
+	Department   *string  `json:"department"`
+	Position     *string  `json:"position"`
+	Phone        *string  `json:"phone"`
+	ProfileImage *string  `json:"profile_image"`
+	IsVerified   bool     `json:"is_verified"`
+	LastLoginAt  *int64   `json:"last_login_at"`
+	UpdatedAt    int64    `json:"updated_at"`
+	CreatedAt    int64    `json:"created_at"`
+	DeviceToken  []string `json:"-"`
 }
 
 type AuthResponse struct {