Gtk & Vte color

• add Gtk & Vte independent control
• improve Gtk & Vte mode behavior

//bug: need trigger context-menu to init plugin

rebase main

• merge #2 #3 from main branch

theme variant

• add theme_variant support
  //so that Vte and Gtk theme mode can be independent control
  //bug: can't distinguish dark_theme and variant
  //bug: not auto load, need open setting first

preview & indicator

• add quick preview (for profile change)
• add status indicator (for current mode)
  //bug: not auto load, need open setting first

setting panel & config save

• add setting_panel
• add config save/load

first release

just work