moved introstate into the state folder

client/src/state/pages/intro.rs

@@ -0,0 +1,26 @@
+// src/state/pages/intro.rs
+use ratatui::style::Modifier;
+
+#[derive(Default, Clone, Debug)]
+pub struct IntroState {
+    pub selected_option: usize,
+}
+
+impl IntroState {
+    pub fn new() -> Self {
+        Self::default()
+    }
+
+    pub fn next_option(&mut self) {
+        self.selected_option = (self.selected_option + 1) % 4;
+    }
+
+    pub fn previous_option(&mut self) {
+        self.selected_option = if self.selected_option == 0 {
+            3
+        } else {
+            self.selected_option - 1
+        };
+    }
+}
+