fix(gui): prevent background apps from stealing focus

[rajanarahul93]

fix(gui): prevent background apps from stealing focus

Summary

This pull request fixes an issue where launching a background application from the terminal would incorrectly steal keyboard focus. The change introduces a condition to the window creation logic, ensuring that only foreground applications receive focus upon launch, thereby preserving the user's context in the terminal.

Root Cause

The UIWindow component was designed to unconditionally grant focus to any newly created window that was marked as visible. This behavior did not differentiate between interactive foreground applications and non-interactive background processes, causing the latter to incorrectly steal focus from the active window.

Changes

• Added a new options.background property to the UIWindow component, which defaults to false.
• Modified the initial window creation logic in UIWindow.js to only call focusWindow() if the options.background property is false.
• Updated two additional event handlers (drop and dragster:enter) to also respect the options.background flag, ensuring focus is not stolen during drag-and-drop operations.

Closes #453