RK Firmware Updater 0.1.1

Maintenance release for the cross-platform Electron GUI

Highlights:

• Prevents closing the app during flash operations
• Avoids hashing large local files in simulation mode
• Adds a User guide button that opens the online guide
• Shows custom configuration warnings and active source hosts before flashing
• Adds configurable long network timeouts
• Improves rkdeveloptool diagnostics, device parsing, and no-device detection
• Expands automated tests to 55 checks, including the online guide link