feat: add poc

src/core/EventBus.js

@@ -0,0 +1,57 @@
+/**
+ * Lightweight EventBus for pub/sub communication between systems
+ */
+export const Events = {
+  // Combat Events
+  DAMAGE_DEALT: 'combat:damage_dealt',
+  ENTITY_DIED: 'combat:entity_died',
+
+  // Evolution Events
+  EVOLVED: 'evolution:evolved',
+  MUTATION_GAINED: 'evolution:mutation_gained',
+
+  // Leveling Events
+  EXP_GAINED: 'stats:exp_gained',
+  LEVEL_UP: 'stats:level_up',
+
+  // Skill Events
+  SKILL_LEARNED: 'skills:learned',
+  SKILL_COOLDOWN_STARTED: 'skills:cooldown_started'
+};
+
+export class EventBus {
+  constructor() {
+    this.listeners = new Map();
+  }
+
+  /**
+     * Subscribe to an event
+     */
+  on(event, callback) {
+    if (!this.listeners.has(event)) {
+      this.listeners.set(event, []);
+    }
+    this.listeners.get(event).push(callback);
+    return () => this.off(event, callback);
+  }
+
+  /**
+     * Unsubscribe from an event
+     */
+  off(event, callback) {
+    if (!this.listeners.has(event)) return;
+    const callbacks = this.listeners.get(event);
+    const index = callbacks.indexOf(callback);
+    if (index > -1) {
+      callbacks.splice(index, 1);
+    }
+  }
+
+  /**
+     * Emit an event
+     */
+  emit(event, data) {
+    if (!this.listeners.has(event)) return;
+    this.listeners.get(event).forEach(callback => callback(data));
+  }
+}