[Feature][Windows][UX] Missing post-launch video loading effect

[shangxinyu1]

Environment

Platform: Windows
Version: Latest (0.1.10 or recent nightly builds)
Comparison: macOS version has this feature implemented

Description

The Windows version is missing the post-launch video loading effect that exists in the macOS version. This creates an inconsistent user experience across platforms.

Current Behavior (Windows)

After launching the application:

• The app window opens immediately
• Content loads directly without any transition effect
• No visual feedback during the initial loading phase
• The experience feels abrupt and less polished

Expected Behavior (Based on macOS)

The macOS version includes a video loading effect after launch:

• A smooth animated transition or video plays during app initialization
• Provides visual feedback that the app is loading
• Creates a more polished and professional first impression
• Serves as a buffer while the application initializes backend services

Impact

Severity: P2 (Medium) - UX enhancement

• Inconsistent user experience between platforms
• Windows feels less polished compared to macOS
• Missed opportunity for branding/visual polish
• Users may perceive Windows version as incomplete or rushed

Suggested Implementation

Port the post-launch video loading effect from macOS to Windows:

• Use the same video assets if possible
• Ensure smooth playback without blocking the UI thread
• Display during initial app initialization (before main window content loads)
• Consider adding a subtle fade transition from video to main content
• Ensure the effect doesn't significantly delay app readiness

Related Issues

• [Bug][Windows][UX] Startup page layout has insufficient spacing and element overlap #889 (Startup page layout issues on Windows) - related to initial launch experience
• [Bug][Desktop] Newly installed client shows a white screen for 3–5 seconds on startup #886 (White screen on startup) - could be masked by a loading effect
• Windows first launch is extremely slow (1 minutes of unresponsiveness after installation) #962 (Update flow finishing state) - related to transition/loading feedback

Additional Notes

This feature would help:

• Create parity with the macOS experience
• Improve perceived performance during cold starts
• Provide consistent branding across platforms
• Reduce user anxiety during initial loading