proxytool_gui: App nhan parent de nhung vao Notebook tab

proxytool_gui: them toggle 'chi giu ✅ Tot' khi copy/luu

proxytool_gui: them ~26 nguon proxy free (http/socks4/socks5), fetch search ip:port linh hoat

add proxytool_gui.py — GUI tim+check+cham diem proxy cho tool mail (stdlib tkinter)