Add macos/ios app using rust lib

src/main.rs

@@ -1,7 +1,7 @@
 use std::{collections::HashMap, error::Error, io::Write, path::PathBuf};
 
 use clap::{Parser, Subcommand};
-use coster_rs::{CsvCost, Unit};
+use coster_rs::CsvCost;
 use serde::Deserialize;
 
 #[derive(Parser)]
@@ -79,7 +79,7 @@ fn move_money(
     coster_rs::move_money(
         csv::Reader::from_path(rules)?,
         csv::Reader::from_path(lines)?,
-        csv::Writer::from_path(output.unwrap_or(PathBuf::from("output.csv")))?,
+        &mut csv::Writer::from_path(output.unwrap_or(PathBuf::from("output.csv")))?,
         use_numeric_accounts,
     )
 }