refactor(P1-1): consolidate canvas event listeners in GUIAdapter

- Remove initEventListeners() from CircuitRenderer (was duplicate)
- GUIAdapter is now single owner of all canvas listeners
- Wire wheel→zoom, MMB pan, hover, dblclick, mouseleave through GUIAdapter
- Clean up dispose() to use stable _boundPerformRender reference
- Remove dead panStartX/panStartY code from GUIAdapter

448 tests passing, build OK.

Author: jurra

src/gui/adapters/GUIAdapter.js

@@ -344,8 +344,8 @@ export class GUIAdapter {
    * Leaves normal scrolling alone if Ctrl is not pressed.
    */
   bindWheelZoom() {
-    // Let CircuitRenderer handle wheel events directly - it has its own zoom method
-    // No need to bind wheel events here as CircuitRenderer.initEventListeners() handles them
+    this._onWheel = (event) => this.circuitRenderer.zoom(event);
+    this.canvas.addEventListener("wheel", this._onWheel);
   }
 
   /**
@@ -545,8 +545,7 @@ export class GUIAdapter {
     this.canvas.addEventListener("mousedown", (event) => {
       if (event.button === 1) {
         this.canvas.style.cursor = "grabbing";
-        this.panStartX = event.clientX - this.circuitRenderer.offsetX;
-        this.panStartY = event.clientY - this.circuitRenderer.offsetY;
+        this.circuitRenderer.startPan(event);
         return;
       }
 
@@ -633,6 +632,10 @@ export class GUIAdapter {
 
     // Move / live placement preview / command move
     this.canvas.addEventListener("mousemove", (event) => {
+      // Delegate panning and hover detection to the renderer first
+      this.circuitRenderer.pan(event);
+      this.circuitRenderer.handleMouseMove(event);
+
       const { offsetX, offsetY } = this.getTransformedMousePosition(event);
 
       // Always track current mouse position for immediate element placement
@@ -684,6 +687,7 @@ export class GUIAdapter {
     this.canvas.addEventListener("mouseup", (event) => {
       if (event.button === 1) {
         this.canvas.style.cursor = "default";
+        this.circuitRenderer.stopPan();
         return;
       }
 
@@ -762,6 +766,17 @@ export class GUIAdapter {
         this.resetCursor();
       }
     });
+
+    // Mouse leave → stop panning and clear hover highlights
+    this.canvas.addEventListener("mouseleave", () => {
+      this.circuitRenderer.stopPan();
+      this.circuitRenderer.clearAllHovers();
+    });
+
+    // Double-click → open property panel (delegates element detection to renderer)
+    this.canvas.addEventListener("dblclick", (event) => {
+      this.circuitRenderer.handleDoubleClick(event);
+    });
   }
 
   /**

src/gui/renderers/CircuitRenderer.js

@@ -108,28 +108,11 @@ export class CircuitRenderer {
         this.circuitService.on('elementMoved', () => this.invalidateSpatialIndex());
         this.circuitService.on('circuitCleared', () => this.invalidateSpatialIndex());
 
-        // Attach Event Listeners
-        this.initEventListeners();
+        // NOTE: Canvas event listeners (wheel, mouse*, dblclick) are NOT registered here.
+        // GUIAdapter is the single owner of all canvas event listeners and calls
+        // our methods (zoom, startPan, pan, stopPan, handleMouseMove, etc.) directly.
     }
 
-    /**
-     * Initializes event listeners for zooming, panning, and double-click property editing.
-     */
-    initEventListeners() {
-        this.canvas.addEventListener("wheel", (event) => this.zoom(event));
-        this.canvas.addEventListener("mousedown", (event) => this.startPan(event));
-        this.canvas.addEventListener("mousemove", (event) => {
-            this.pan(event);
-            this.handleMouseMove(event);
-        });
-        this.canvas.addEventListener("mouseup", () => this.stopPan());
-        this.canvas.addEventListener("mouseleave", () => {
-            this.stopPan();
-            this.clearAllHovers();
-        });
-        this.canvas.addEventListener("dblclick", (event) => this.handleDoubleClick(event));
-    }
-
     /**
      * Clears the canvas by resetting its drawing context.
      */
@@ -609,23 +592,14 @@ export class CircuitRenderer {
      * Cleanup method to remove event listeners and prevent memory leaks
      */
     dispose() {
-        // Remove all canvas event listeners
-        this.canvas.removeEventListener("wheel", this.zoom);
-        this.canvas.removeEventListener("mousedown", this.startPan);
-        this.canvas.removeEventListener("mousemove", this.handleMouseMove);
-        this.canvas.removeEventListener("mouseup", this.stopPan);
-        this.canvas.removeEventListener("mouseleave", this.clearAllHovers);
-        this.canvas.removeEventListener("dblclick", this.handleDoubleClick);
-        
         // Clear any scheduled renders
-        globalRenderScheduler.cancelRender(this.performRender);
+        globalRenderScheduler.cancelRender(this._boundPerformRender);
 
         // Clear references
         this.renderers.clear();
         this.selectedElements.clear();
         this.hoveredElement = null;
         this.selectedElement = null;
-        
     }
 
     /**