Add player controls (X/C keys) + generate 38 new assets (195 total)

- Implemented X key for chopping action (handleChoppingAction)
- Implemented C key for mining action (handleMiningAction)
- Added silver arrows to inventory (10x)
- Generated 38 new PNG assets:
  * Trees: pine, oak, maple
  * Crops: carrot, tomato, pumpkin, pepper, cabbage
  * Buildings: silo, composter
  * Environment: rock, bush, daisy, log, pond, stump, berries
  * Tools: iron sword, scythe, fishing rod, shovel, boots, stone, wood
  * Food/Items: cheese, milk, egg, fertilizer, hay bale
  * Lighting: torch, lantern
  * Animals: hedgehog, horse, sheep, pig, bat, owl

src/systems/InventorySystem.js

@@ -18,6 +18,7 @@ class InventorySystem {
         this.addItem('hoe', 1);
         this.addItem('watering_can', 1); // 💧 Zalivalka
         this.addItem('seeds', 5);    // Zmanjšano število semen
+        this.addItem('arrow_silver', 10);  // ➶ Silver arrows for werewolf hunting
         // Removed default wood/stone so player has to gather them
 
         this.gold = 0;