examples,builtin,cgen,live: fix windows hot reload with -cc tcc, improve the infrastructure, use a V global instead of a C one (fix #23214) (#23350)

examples/hot_reload/message.v

@@ -4,15 +4,25 @@ module main
 import time
 import v.live
 
+struct App {
+mut:
+	x       int
+	counter int
+}
+
 @[live]
-fn print_message() {
-	info := live.info()
-	println('OK reloads: ${info.reloads_ok:4d} | Total reloads: ${info.reloads:4d} | Hello! Modify this message while the program is running.')
+fn print_message(mut app App) {
+	i := live.info()
+	println('OK reloads: ${i.reloads_ok:4d} | Total reloads: ${i.reloads:4d} | Hello! Modify this message while the program is running. app: ${voidptr(app)} | app.x: ${app.x:6} | app.counter: ${app.counter:6}')
+	// app.x = 99 // try changing this to another value, while the program is running ...
+	app.counter++
 }
 
 fn main() {
+	unbuffer_stdout()
+	mut app := &App{}
 	for {
-		print_message()
+		print_message(mut app)
 		time.sleep(500 * time.millisecond)
 	}
 }