- main window now use UI file for layout.
- remove all manual computed widget position code. use full Qt layout implementation instead.
- remove useless functions in main window
- change style changed slot as private
- change default dark theme to light
- disable dark mode on windows 10 because Qt's windows 11 theme has bad support on windows 10 (icon display error)
- level required minimum qt version up to 6.5 for color schema.