Adds edge scroll functionality for drag interactions

Implements EdgeScrollManager to enable automatic scrolling during drag operations

Introduces new scroll management system that:
- Detects mouse proximity to container edges
- Provides variable scroll speed based on mouse position
- Compensates dragged elements during scrolling

Enhances drag-and-drop user experience with smooth scrolling

src/v2/demo/DemoApp.ts

@@ -8,6 +8,7 @@ import { IndexedDBContext } from '../storage/IndexedDBContext';
 import { DataSeeder } from '../workers/DataSeeder';
 import { ViewConfig } from '../core/ViewConfig';
 import { DragDropManager } from '../managers/DragDropManager';
+import { EdgeScrollManager } from '../managers/EdgeScrollManager';
 
 export class DemoApp {
   private animator!: NavigationAnimator;
@@ -23,7 +24,8 @@ export class DemoApp {
     private headerDrawerManager: HeaderDrawerManager,
     private indexedDBContext: IndexedDBContext,
     private dataSeeder: DataSeeder,
-    private dragDropManager: DragDropManager
+    private dragDropManager: DragDropManager,
+    private edgeScrollManager: EdgeScrollManager
   ) {}
 
   async init(): Promise<void> {
@@ -55,6 +57,10 @@ export class DemoApp {
     // Init drag-drop
     this.dragDropManager.init(this.container);
 
+    // Init edge scroll
+    const scrollableContent = this.container.querySelector('swp-scrollable-content') as HTMLElement;
+    this.edgeScrollManager.init(scrollableContent);
+
     // Setup event handlers
     this.setupNavigation();
     this.setupDrawerToggle();