feat(schema): restore complete Ent schema files

ent/schema/permission.go

@@ -1,6 +1,10 @@
 package schema
 
-import "entgo.io/ent"
+import (
+	"entgo.io/ent"
+	"entgo.io/ent/schema/edge"
+	"entgo.io/ent/schema/field"
+)
 
 // Permission holds the schema definition for the Permission entity.
 type Permission struct {
@@ -9,10 +13,20 @@ type Permission struct {
 
 // Fields of the Permission.
 func (Permission) Fields() []ent.Field {
-	return nil
+	return []ent.Field{
+		field.String("id").
+			Unique().
+			Immutable(),
+		field.String("name").
+			Unique().
+			NotEmpty().
+			Comment("Format: module.resource.action"),
+	}
 }
 
 // Edges of the Permission.
 func (Permission) Edges() []ent.Edge {
-	return nil
+	return []ent.Edge{
+		edge.To("role_permissions", RolePermission.Type),
+	}
 }