feat(tui): add assistant message steps counter to sidebar

tui/src/app.rs

@@ -64,6 +64,8 @@ pub struct AppState {
     pub collapsed_messages_scroll: usize,
     pub collapsed_messages_selected: usize,
     pub has_user_messages: bool,
+    /// Count of assistant message rounds/steps in the current session
+    pub assistant_message_count: usize,
     /// Per-message rendered line cache for efficient incremental rendering
     pub per_message_cache: PerMessageCache,
     /// Assembled lines cache (the final combined output of all message lines)
@@ -384,6 +386,7 @@ impl AppState {
             mouse_capture_enabled: false, // Will be set based on terminal detection in event_loop
             loading_manager: LoadingStateManager::new(),
             has_user_messages: false,
+            assistant_message_count: 0,
             message_tool_calls: None,
             approval_bar: ApprovalBar::new(),
             message_approved_tools: Vec::new(),

tui/src/services/handlers/message.rs

@@ -63,6 +63,7 @@ pub fn handle_stream_message(
         state
             .messages
             .push(Message::assistant(Some(id), s.clone(), None));
+        state.assistant_message_count += 1;
         state.text_area.set_text("");
 
         if !was_at_bottom {

tui/src/services/handlers/misc.rs

@@ -304,6 +304,7 @@ pub fn handle_end_loading_operation(state: &mut AppState, operation: crate::app:
 /// Handle assistant message event
 pub fn handle_assistant_message(state: &mut AppState, msg: String) {
     state.messages.push(Message::assistant(None, msg, None));
+    state.assistant_message_count += 1;
 
     // Invalidate cache since messages changed
     crate::services::message::invalidate_message_lines_cache(state);

tui/src/services/side_panel.rs

@@ -70,7 +70,7 @@ pub fn render_side_panel(f: &mut Frame, state: &mut AppState, area: Rect) {
     let context_height = if context_collapsed {
         collapsed_height
     } else {
-        5 // Header + Tokens + Model + Provider
+        6 // Header + Tokens + Model + Provider + Steps
     };
 
     // Billing section is hidden when billing_info is None (local mode)
@@ -193,6 +193,14 @@ fn render_context_section(f: &mut Frame, state: &AppState, area: Rect, collapsed
         .unwrap_or_default();
     let max_tokens = context_info.max_tokens as u32;
 
+    // Steps - show assistant message count (rounds/steps)
+    let steps_value = if state.assistant_message_count == 0 {
+        "N/A".to_string()
+    } else {
+        state.assistant_message_count.to_string()
+    };
+    lines.push(make_row("Steps", steps_value, Color::White));
+
     // Show N/A when no content yet (tokens == 0)
     if tokens == 0 {
         lines.push(make_row("Tokens", "N/A".to_string(), Color::DarkGray));