feat: Replace mongo package with monc & mon (#2002)

* Replace mongo package with monc & mon

* Add terminal whitespace

* format code

tools/goctl/model/mongo/template/model_custom.tpl

@@ -0,0 +1,28 @@
+package model
+
+{{if .Cache}}import (
+    "github.com/zeromicro/go-zero/core/stores/cache"
+    "github.com/zeromicro/go-zero/core/stores/monc"
+){{else}}import "github.com/zeromicro/go-zero/core/stores/mon"{{end}}
+
+var _ {{.Type}}Model = (*custom{{.Type}}Model)(nil)
+
+type (
+    // {{.Type}}Model is an interface to be customized, add more methods here,
+    // and implement the added methods in custom{{.Type}}Model.
+    {{.Type}}Model interface {
+        {{.lowerType}}Model
+    }
+
+    custom{{.Type}}Model struct {
+        *default{{.Type}}Model
+    }
+)
+
+// New{{.Type}}Model returns a model for the mongo.
+func New{{.Type}}Model(url, db, collection string{{if .Cache}}, c cache.CacheConf{{end}}) {{.Type}}Model {
+    conn := {{if .Cache}}monc{{else}}mon{{end}}.MustNewModel(url, db, collection{{if .Cache}}, c{{end}})
+    return &custom{{.Type}}Model{
+        default{{.Type}}Model: newDefault{{.Type}}Model(conn),
+    }
+}