test: add test screen function

lua/CC Tweaked/tutel/tutel-host.lua

@@ -178,7 +178,22 @@ log.general("tutel host init")
 sendToAll("SCAN", { ["hostChannel"] = HOST_CHANNEL })
 log.info("broadcasted scan message")
 
+-- while true do
+--     pollAndProcessEvents()
+-- end
 
-while true do
-    pollAndProcessMessages()
+function updateScreen()
+    local w, h = term.getSize()
+
+    term.clear()
+    term.setCursorPos(0, 0)
+
+    local title = "tutel host controller"
+    local titleStart = (w / 2) - (title:len() / 2)
+    term.setBackgroundColour(colours.red)
+    term.clearLine()
+    term.setCursorPos(titleStart, 0)
+    term.write(title)
 end
+
+updateScreen()