Start work on porting unicode input kitten to Go

tools/cmd/tool/main.go

@@ -10,6 +10,7 @@ import (
 	"kitty/tools/cmd/clipboard"
 	"kitty/tools/cmd/edit_in_kitty"
 	"kitty/tools/cmd/icat"
+	"kitty/tools/cmd/unicode_input"
 	"kitty/tools/cmd/update_self"
 	"kitty/tools/tui"
 )
@@ -29,6 +30,8 @@ func KittyToolEntryPoints(root *cli.Command) {
 	clipboard.EntryPoint(root)
 	// icat
 	icat.EntryPoint(root)
+	// unicode_input
+	unicode_input.EntryPoint(root)
 	// __hold_till_enter__
 	root.AddSubCommand(&cli.Command{
 		Name:            "__hold_till_enter__",