feat(root): stop showing suggestion when delete entire line

.gitignore

@@ -1,2 +1,3 @@
 iris
-iris.log
+iris.log
+autocomplete

root/root.go

@@ -287,8 +287,10 @@ func runWrapper() {
 		if !suggestionsEnabled {
 			return
 		}
-		// don't render if shell is starting up
-		if isReload && naiveBuffer == "" {
+		
+		// If buffer is empty (e.g. backspace to 0 or after reload), clear overlay immediately
+		if naiveBuffer == "" {
+			os.Stdout.Write([]byte(overlay.ClearAndDisable()))
 			return
 		}
 
@@ -309,6 +311,9 @@ func runWrapper() {
 		}
 	}
 
+	// Trigger initial render to clear any potential artifacts from previous session
+	renderOverlay()
+
 	for {
 		inputSlice := make([]byte, 128)
 		n, err := os.Stdin.Read(inputSlice)