feat: Prevent form navigation with unsaved changes

client/src/components/handlers/canvas.rs

@@ -27,13 +27,16 @@ pub fn render_canvas(
         .split(area);
 
     // Input container styling
+    let border_style = if form_state.has_unsaved_changes() {
+        Style::default().fg(theme.warning)
+    } else if is_edit_mode {
+        Style::default().fg(theme.accent)
+    } else {
+        Style::default().fg(theme.secondary)
+    };
     let input_container = Block::default()
         .borders(Borders::ALL)
-        .border_style(if is_edit_mode {
-            form_state.has_unsaved_changes().then(|| theme.warning).unwrap_or(theme.accent)
-        } else {
-            theme.secondary
-        })
+        .border_style(border_style)
         .style(Style::default().bg(theme.bg));
 
     // Input block dimensions

client/src/tui/functions/form.rs

@@ -11,6 +11,15 @@ pub async fn handle_action(
     total_count: u64,
     ideal_cursor_column: &mut usize,
 ) -> Result<String, Box<dyn std::error::Error>> {
+            // TODO store unsaved changes without deleting form state values
+    // First check for unsaved changes in both cases
+    if form_state.has_unsaved_changes() {
+        return Ok(
+            "Unsaved changes. Save (Ctrl+S) or Revert (Ctrl+R) before navigating."
+                .to_string(),
+        );
+    }
+
     match action {
         "previous_entry" => {
             let new_position = current_position.saturating_sub(1);