cgen: support string interpolation in ORM queries (#17141)

vlib/orm/orm_string_interpolation_in_where_test.v

@@ -0,0 +1,36 @@
+import db.sqlite
+
+struct User {
+	id   int    [primary; sql: serial]
+	name string
+}
+
+fn test_string_interpolation() {
+	mut db := sqlite.connect(':memory:') or { panic(err) }
+
+	sql db {
+		create table User
+	}
+
+	user_suffix := '_user'
+
+	first_user := User{
+		name: 'first${user_suffix}'
+	}
+
+	second_user := User{
+		name: 'second${user_suffix}'
+	}
+
+	sql db {
+		insert first_user into User
+		insert second_user into User
+	}
+
+	users := sql db {
+		select from User where name == 'first${user_suffix}'
+	}
+
+	assert users.len == 1
+	assert users.first().name == 'first${user_suffix}'
+}