feat(chat): Add terminal bell notifications

Add terminal bell notifications when responses are ready or spinner drops.

🤖 Assisted by [Amazon Q Developer](https://aws.amazon.com/q/developer)

Author: somarsai

crates/q_cli/src/cli/chat/mod.rs

@@ -102,6 +102,7 @@ use crate::cli::chat::parse::{
 };
 use crate::util::region_check;
 use crate::util::token_counter::TokenCounter;
+use crate::util::spinner::play_notification_bell;
 
 const WELCOME_TEXT: &str = color_print::cstr! {"
 
@@ -1686,7 +1687,10 @@ where
                     )
                     .await;
                 }
+
                 if self.interactive {
+                    // Play notification bell when response is complete
+                    play_notification_bell();
                     queue!(self.output, style::ResetColor, style::SetAttribute(Attribute::Reset))?;
                     execute!(self.output, style::Print("\n"))?;
 

crates/q_cli/src/util/spinner.rs

@@ -7,9 +7,12 @@ use std::sync::mpsc::{
     TryRecvError,
     channel,
 };
-use std::thread;
 use std::thread::JoinHandle;
 use std::time::Duration;
+use std::{
+    env,
+    thread,
+};
 
 use anstream::{
     print,
@@ -49,6 +52,53 @@ pub enum SpinnerComponent {
     Spinner,
 }
 
+/// Play the terminal bell notification sound
+/// This is a separate function to make it easier to call from multiple places
+pub fn play_notification_bell() {
+    // Check if we should play the bell based on terminal type
+    if should_play_bell() {
+        print!("\x07"); // ASCII bell character
+        stdout().flush().unwrap();
+    }
+}
+
+/// Determine if we should play the bell based on terminal type
+fn should_play_bell() -> bool {
+    // Get the TERM environment variable
+    if let Ok(term) = env::var("TERM") {
+        // List of terminals known to handle bell character well
+        let bell_compatible_terms = [
+            "xterm",
+            "xterm-256color",
+            "screen",
+            "screen-256color",
+            "tmux",
+            "tmux-256color",
+            "rxvt",
+            "rxvt-unicode",
+            "linux",
+            "konsole",
+            "gnome",
+            "gnome-256color",
+            "alacritty",
+            "iterm2",
+        ];
+
+        // Check if the current terminal is in the compatible list
+        for compatible_term in bell_compatible_terms.iter() {
+            if term.starts_with(compatible_term) {
+                return true;
+            }
+        }
+
+        // For other terminals, don't play the bell
+        return false;
+    }
+
+    // If TERM is not set, default to not playing the bell
+    false
+}
+
 impl Spinner {
     pub fn new(components: Vec<SpinnerComponent>) -> Self {
         let (sender, recv) = channel::<Option<String>>();