Provide default auto-scope prompt and confirmation dialog

codex-rs/tui/src/chatwidget.rs

@@ -2191,6 +2191,19 @@ impl ChatWidget {
             }
         }
 
+        let mut scope_prompt = scope_prompt;
+        if resolved_paths.is_empty() && scope_prompt.is_none() {
+            let default_prompt = match mode {
+                SecurityReviewMode::Full => {
+                    "Identify the most security-relevant directories (3-8) for a comprehensive review. Focus on production services, externally reachable interfaces, auth/authz modules, secret management, and critical infrastructure. Exclude tests, vendor bundles, docs, and generated files."
+                }
+                SecurityReviewMode::Bugs => {
+                    "Suggest the smallest set of directories (3-8) most likely to contain exploitable bugs. Prioritise request parsing, input validation, authentication, authorisation, and secret handling. Skip tests, vendor bundles, docs, and generated files."
+                }
+            };
+            scope_prompt = Some(default_prompt.to_string());
+        }
+
         let mut context_paths = display_paths.clone();
         if context_paths.is_empty()
             && let Some(prompt) = scope_prompt.as_ref()