Organize backend into product executable and shared Go modules

backend/shared/database/repository/builder/keyword.go

@@ -0,0 +1,16 @@
+package builder
+
+type MongoKeyword string
+
+const (
+	MKAs                         MongoKeyword = "as"
+	MKForeignField               MongoKeyword = "foreignField"
+	MKFrom                       MongoKeyword = "from"
+	MKIncludeArrayIndex          MongoKeyword = "includeArrayIndex"
+	MKLet                        MongoKeyword = "let"
+	MKLocalField                 MongoKeyword = "localField"
+	MKPath                       MongoKeyword = "path"
+	MKPipeline                   MongoKeyword = "pipeline"
+	MKPreserveNullAndEmptyArrays MongoKeyword = "preserveNullAndEmptyArrays"
+	MKNewRoot                    MongoKeyword = "newRoot"
+)