feat: show sidetone level in Waybar tooltip

Tooltip now shows "HS80: 42% — Discharging | Sidetone: 10/23" when
the ALSA sidetone control is available. Falls back gracefully to
battery-only tooltip when sidetone cannot be read.

Bump version to 0.1.1.

src/main.rs

@@ -58,7 +58,8 @@ fn run() -> error::Result<()> {
             let device = bragi::BragiDevice::open_with_verbose(cli.verbose)?;
             let level = device.battery_level()?;
             let status = device.battery_status()?;
-            println!("{}", output::format_waybar_json(level, &status));
+            let sidetone = sidetone::get_level().ok();
+            println!("{}", output::format_waybar_json(level, &status, sidetone));
         }
 
         Command::Udev => {

src/output.rs

@@ -26,7 +26,7 @@ pub fn format_info(vid: u16, pid: u16, fw_app: u16, fw_build: u16) -> String {
 /// Formatiert Waybar-kompatibles JSON.
 ///
 /// Waybar erwartet: {"text": "...", "tooltip": "...", "class": "...", "percentage": N}
-pub fn format_waybar_json(level: f32, status: &BatteryStatus) -> String {
+pub fn format_waybar_json(level: f32, status: &BatteryStatus, sidetone: Option<i64>) -> String {
     let icon = status.icon();
     let label = status.label();
     let percentage = level.round() as u32;
@@ -41,9 +41,14 @@ pub fn format_waybar_json(level: f32, status: &BatteryStatus) -> String {
         BatteryStatus::Unknown(_) => "unknown",
     };
 
+    let tooltip = match sidetone {
+        Some(st) => format!("HS80: {percentage}% — {label} | Sidetone: {st}/23"),
+        None => format!("HS80: {percentage}% — {label}"),
+    };
+
     let json = serde_json::json!({
         "text": format!("{icon} {percentage}%"),
-        "tooltip": format!("HS80: {percentage}% — {label}"),
+        "tooltip": tooltip,
         "class": class,
         "percentage": percentage,
     });