style: cargo fmt --all — make codebase rustfmt-clean

First run of the build-and-test CI gate (cargo fmt --all -- --check) surfaced
pre-existing formatting drift across the agent and server crates. Apply rustfmt
across the workspace so the codebase meets its own CI gate. Pure formatting; no
logic changes.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

agent/src/viewer/mod.rs

@@ -11,7 +11,7 @@ use crate::proto;
 use anyhow::Result;
 use std::sync::Arc;
 use tokio::sync::{mpsc, Mutex};
-use tracing::{info, error, warn};
+use tracing::{error, info, warn};
 
 #[derive(Debug, Clone)]
 pub enum ViewerEvent {
@@ -93,16 +93,18 @@ pub async fn run(server_url: &str, session_id: &str, api_key: &str) -> Result<()
                     }
                 }
                 Some(proto::message::Payload::CursorPosition(pos)) => {
-                    let _ = viewer_tx_recv.send(ViewerEvent::CursorPosition(
-                        pos.x, pos.y, pos.visible
-                    )).await;
+                    let _ = viewer_tx_recv
+                        .send(ViewerEvent::CursorPosition(pos.x, pos.y, pos.visible))
+                        .await;
                 }
                 Some(proto::message::Payload::CursorShape(shape)) => {
                     let _ = viewer_tx_recv.send(ViewerEvent::CursorShape(shape)).await;
                 }
                 Some(proto::message::Payload::Disconnect(d)) => {
                     warn!("Server disconnected: {}", d.reason);
-                    let _ = viewer_tx_recv.send(ViewerEvent::Disconnected(d.reason)).await;
+                    let _ = viewer_tx_recv
+                        .send(ViewerEvent::Disconnected(d.reason))
+                        .await;
                     break;
                 }
                 _ => {}