Add tool use to the orchestrator (#4)

Add tool use without sandboxing.

Currently available tools are list dir, read file, write file and exec bash.

Reviewed-on: #4
Co-authored-by: Drew Galbraith <drew@tiramisu.one>
Co-committed-by: Drew Galbraith <drew@tiramisu.one>

src/tui/mod.rs

@@ -72,6 +72,8 @@ pub struct AppState {
     pub viewport_height: u16,
     /// Transient error message shown in the status bar, cleared on next keypress.
     pub status_error: Option<String>,
+    /// A tool approval request waiting for user input (y/n).
+    pub pending_approval: Option<events::PendingApproval>,
 }
 
 impl AppState {
@@ -85,6 +87,7 @@ impl AppState {
             pending_keys: Vec::new(),
             viewport_height: 0,
             status_error: None,
+            pending_approval: None,
         }
     }
 }
@@ -185,6 +188,17 @@ pub async fn run(
             Some(input::LoopControl::ClearHistory) => {
                 let _ = action_tx.send(UserAction::ClearHistory).await;
             }
+            Some(input::LoopControl::ToolApproval {
+                tool_use_id,
+                approved,
+            }) => {
+                let _ = action_tx
+                    .send(UserAction::ToolApprovalResponse {
+                        tool_use_id,
+                        approved,
+                    })
+                    .await;
+            }
             None => {}
         }
     }