feat: track total berries earned in session and savegames (#61)

tests/common/mod.rs

@@ -2,6 +2,7 @@ use bevy::prelude::*;
 use pomomon_garden::features::config::components::{BerrySeedConfig, GameConfig};
 use pomomon_garden::features::grid::components::{Grid, Tile, TileState};
 use pomomon_garden::features::inventory::components::{Inventory, ItemStack, ItemType};
+use pomomon_garden::features::phase::components::SessionTracker;
 
 pub fn setup_app(
     grid_width: u32,
@@ -64,6 +65,8 @@ pub fn setup_app(
         berry_seeds: seeds,
         ..Default::default()
     });
+    
+    app.init_resource::<SessionTracker>();
 
     app
 }