Add Contact Management Functionality

- Introduced a new contact management feature, including the ability to create, retrieve, search, update, and delete contact messages.
- Implemented the Contact entity, repository, service, and handler layers following Clean Architecture principles.
- Added API endpoints for contact operations in Swagger documentation, ensuring comprehensive API specifications.
- Enhanced error handling and validation for contact data, improving robustness and user experience.
- Updated the main application to initialize the contact repository and service, integrating them into the existing system.

internal/contact/entity.go

@@ -0,0 +1,75 @@
+package contact
+
+import (
+	"tm/pkg/mongo"
+
+	"go.mongodb.org/mongo-driver/v2/bson"
+)
+
+// ContactStatus represents the status of a contact message
+type ContactStatus string
+
+const (
+	ContactStatusPending    ContactStatus = "pending"
+	ContactStatusInProgress ContactStatus = "in_progress"
+	ContactStatusResolved   ContactStatus = "resolved"
+	ContactStatusClosed     ContactStatus = "closed"
+)
+
+// Contact represents a contact us message in the system
+type Contact struct {
+	mongo.Model `bson:",inline"`
+	FullName    string        `bson:"full_name" json:"full_name" validate:"required"`
+	Email       string        `bson:"email" json:"email" validate:"required,email"`
+	Phone       string        `bson:"phone" json:"phone" validate:"required"`
+	Message     string        `bson:"message" json:"message" validate:"required"`
+	Status      ContactStatus `bson:"status" json:"status" validate:"required,oneof=pending in_progress resolved closed"`
+	AdminNotes  *string       `bson:"admin_notes,omitempty" json:"admin_notes,omitempty"`
+	ResolvedAt  *int64        `bson:"resolved_at,omitempty" json:"resolved_at,omitempty"`
+	ResolvedBy  *string       `bson:"resolved_by,omitempty" json:"resolved_by,omitempty"`
+}
+
+// SetID sets the contact ID (implements IDSetter interface)
+func (c *Contact) SetID(id string) {
+	c.ID, _ = bson.ObjectIDFromHex(id)
+}
+
+// GetID returns the contact ID (implements IDGetter interface)
+func (c *Contact) GetID() string {
+	return c.ID.Hex()
+}
+
+// SetCreatedAt sets the created timestamp (implements Timestamp interface)
+func (c *Contact) SetCreatedAt(timestamp int64) {
+	c.CreatedAt = timestamp
+}
+
+// SetUpdatedAt sets the updated timestamp (implements Timestamp interface)
+func (c *Contact) SetUpdatedAt(timestamp int64) {
+	c.UpdatedAt = timestamp
+}
+
+// GetCreatedAt returns the created timestamp (implements Timestamp interface)
+func (c *Contact) GetCreatedAt() int64 {
+	return c.CreatedAt
+}
+
+// GetUpdatedAt returns the updated timestamp (implements Timestamp interface)
+func (c *Contact) GetUpdatedAt() int64 {
+	return c.UpdatedAt
+}
+
+// IsPending returns true if the contact is pending
+func (c *Contact) IsPending() bool {
+	return c.Status == ContactStatusPending
+}
+
+// IsResolved returns true if the contact is resolved
+func (c *Contact) IsResolved() bool {
+	return c.Status == ContactStatusResolved || c.Status == ContactStatusClosed
+}
+
+// CanBeUpdated returns true if the contact can be updated
+func (c *Contact) CanBeUpdated() bool {
+	return c.Status != ContactStatusClosed
+}