feat: add normalized config tracking and improve command

- Add normalize_to_final_build() to map tune configs to final builds (323/233/332)
- Add normalized_config field to BestCarRecord
- Change CarCounts.by_rid key from String to (String, String) for per-config tracking
- Change CarCounts.guid_to_rid to HashMap<String, HashSet<(String, String)>>
- Extract owned tune configs from my_cars.json (engineMajor/weightMajor/chassisMajor)
- Add improve command: owned cars not yet at final build, sorted by track count
- Strip version prefixes (v2c_/v1c_) from config keys at parse time
- Update dedup check in update_best_car to consider normalized_config
- Add atomic_write helper for safe CSV output
- Delete completed plans/code-review-v2.md
- Apply rustfmt formatting across codebase

src/commands/best.rs

@@ -9,9 +9,15 @@ use crate::commands::{load_my_cars_or_warn, run_analysis};
 use crate::output::{write_best_csv, write_very_best_csv};
 
 /// Executes the best command: generates best.csv and very_best.csv.
-pub async fn run_best(my_cars_path: &str, cars_db_path: &str, times_dir: &str, output_dir: &str, min_count: usize) -> Result<(), AppError> {
+pub async fn run_best(
+    my_cars_path: &str,
+    cars_db_path: &str,
+    times_dir: &str,
+    output_dir: &str,
+    min_count: usize,
+) -> Result<(), AppError> {
     let my_data = load_my_cars_or_warn(my_cars_path)?;
-    let (_ctx, counts) = run_analysis(&my_data.owned, cars_db_path, times_dir).await?;
+    let (_ctx, counts) = run_analysis(&my_data, cars_db_path, times_dir).await?;
     write_best_csv(output_dir, &counts)?;
     write_very_best_csv(output_dir, &counts, min_count)?;
     println!("Written: best.csv, very_best.csv");