feat(dashboard): add confirmations, fix UX issues, and optimize grid rendering

BREAKING CHANGE: applyDashboardConfig() now accepts optional second parameter for optimization

Add auto-arrange confirmation dialog:
- Add warning popup before auto-arranging widgets across all tabs
- Follows same pattern as reset layout confirmation
- Prevents accidental destructive operations

Fix text selection interference:
- Apply user-select: none to entire .rpg-widget in edit mode
- Previously only applied to .rpg-widget-content
- Prevents text selection when dragging widgets, especially in attribute boxes
- Improves drag interaction on both desktop and mobile

Fix edit controls visibility:
- Add CSS rule to completely hide edit controls outside edit mode
- Controls now properly hidden when not in edit mode
- Settings button (⚙) kept for future widget configuration

Fix input disabling in edit mode:
- Call disableContentEditing() after tab switches in onTabChange()
- Call disableContentEditing() in syncAllControls()
- Ensures text fields remain non-editable in edit mode after all operations

Fix resize grid background rendering:
- Copy drag handler grid logic EXACTLY to resize handler
- Use gridEngine.calculateGridHeight(widgets) instead of manual calculation
- Add proper remToPixels() conversions for gap and rowHeight
- Pass widgets array through initWidget() and startResize()
- Grid now renders correctly during resize, matching drag behavior

Optimize layout operations:
- Add skipInitialSwitch option to applyDashboardConfig()
- Prevents redundant clearGrid() calls during resetLayout()
- Defers rendering until after layout calculations complete

Files modified:
- dashboardIntegration.js: Auto-arrange confirmation
- dashboardManager.js: skipInitialSwitch option, input disabling, widgets array
- editModeManager.js: Input disabling in syncAllControls()
- resizeHandler.js: Grid rendering fixes with proper unit conversions
- style.css: Text selection prevention, edit controls visibility

src/systems/dashboard/editModeManager.js

@@ -482,6 +482,9 @@ export class EditModeManager {
             }
         });
 
+        // Ensure content editing is disabled for all widgets
+        this.disableContentEditing();
+
         console.log('[EditModeManager] Synced controls for', widgets.length, 'widgets');
     }