feat(tui): update system message for clarity and conciseness in tool usage instructions

apps/interfaces/tui/src/view/overlays/mod.rs

@@ -16,6 +16,7 @@ pub mod quit_confirm;
 pub mod rewind;
 pub mod settings;
 pub mod todo;
+pub mod plan;
 pub mod usage;
 
 use crate::state::{AppStateRest, Overlay};
@@ -95,6 +96,9 @@ pub fn render_overlay(
         Overlay::Todo => {
             todo::render(frame, overlay_area, block, state);
         }
+        Overlay::Plan => {
+            plan::render(frame, overlay_area, block, state);
+        }
         Overlay::Rewind => {
             rewind::render(frame, overlay_area, block, state);
         }

apps/interfaces/tui/src/view/overlays/plan.rs

@@ -0,0 +1,32 @@
+//! Overlay: Project Plan view — shows the full project plan content.
+use ratatui::style::{Modifier, Style};
+use ratatui::text::Span;
+use ratatui::widgets::{Block, Paragraph, Wrap};
+use ratatui::Frame;
+use crate::view::theme::Theme;
+
+/// Render the Project Plan overlay.
+pub fn render(
+    frame: &mut Frame,
+    area: ratatui::layout::Rect,
+    block: Block<'static>,
+    state: &crate::state::AppStateRest,
+) {
+    let block = block
+        .title(Span::styled(
+            " Project Plan ",
+            Style::default()
+                .fg(Theme::ACCENT_TEAL)
+                .add_modifier(Modifier::BOLD),
+        ))
+        .border_style(Style::default().fg(Theme::ACCENT_TEAL));
+    let content = if state.misc.plan_content.is_empty() {
+        "  No active project plan."
+    } else {
+        &state.misc.plan_content
+    };
+    let paragraph = Paragraph::new(content)
+        .block(block)
+        .wrap(Wrap { trim: false });
+    frame.render_widget(paragraph, area);
+}