refactor: transition to struct-of-arrays ECS architecture

- Replace individual Entity structs with centralized component slices in Game struct (SoA layout).
- Implement bitmask-based component lookup (CM_Position, CM_Move, etc.).
- Convert logic from object-oriented Update() methods to standalone Systems (UpdateMoveSystem, UpdateGatherSystem, UpdateSpawnSystem).
- Update rendering, selection, and input handling to iterate over component arrays.

1 files changed, 3 insertions, 1 deletions

diff --git a/resource.go b/resource.go
index d52a438..5fb48ae 100644
--- a/resource.go
+++ b/resource.go
@@ -2,6 +2,8 @@ package main
 
 import (
 	"time"
+
+	"age_of_empires/ecs"
 )
 
 type ResourceSource struct {
@@ -11,7 +13,7 @@ type ResourceSource struct {
 type ResourceGatherer struct {
 	MaxCapacity    int
 	CurrentVolume  int
-	CurrentTarget  *Entity
+	Source         ecs.Entity
 	LastPickupTime time.Time
 }