add context window monitor

Writes the current context window to logs/current_context_window (uses a symlink to a session ID).

This PR was unfortunately generated by a different LLM and did a ton of superficial reformating, it's actually a fairly small and benign change, but I don't want to roll back everything. Hope that's ok.

crates/g3-computer-control/examples/test_window_capture.rs

@@ -3,36 +3,46 @@ use g3_computer_control::create_controller;
 #[tokio::main]
 async fn main() {
     println!("Testing window-specific screenshot capture...");
-    
+
     let controller = create_controller().expect("Failed to create controller");
-    
+
     // Test 1: Capture iTerm2 window
     println!("\n1. Capturing iTerm2 window...");
-    match controller.take_screenshot("/tmp/iterm_window.png", None, Some("iTerm2")).await {
+    match controller
+        .take_screenshot("/tmp/iterm_window.png", None, Some("iTerm2"))
+        .await
+    {
         Ok(_) => {
             println!("   ✅ iTerm2 window captured to /tmp/iterm_window.png");
-            let _ = std::process::Command::new("open").arg("/tmp/iterm_window.png").spawn();
+            let _ = std::process::Command::new("open")
+                .arg("/tmp/iterm_window.png")
+                .spawn();
         }
         Err(e) => println!("   ❌ Failed: {}", e),
     }
-    
+
     // Wait a moment for the image to open
     tokio::time::sleep(tokio::time::Duration::from_secs(2)).await;
-    
+
     // Test 2: Full screen capture for comparison
     println!("\n2. Capturing full screen for comparison...");
-    match controller.take_screenshot("/tmp/fullscreen.png", None, None).await {
+    match controller
+        .take_screenshot("/tmp/fullscreen.png", None, None)
+        .await
+    {
         Ok(_) => {
             println!("   ✅ Full screen captured to /tmp/fullscreen.png");
-            let _ = std::process::Command::new("open").arg("/tmp/fullscreen.png").spawn();
+            let _ = std::process::Command::new("open")
+                .arg("/tmp/fullscreen.png")
+                .spawn();
         }
         Err(e) => println!("   ❌ Failed: {}", e),
     }
-    
+
     println!("\n=== Comparison ===");
     println!("iTerm window:  /tmp/iterm_window.png (should show ONLY iTerm window)");
     println!("Full screen:   /tmp/fullscreen.png (should show entire desktop)");
-    
+
     // Show file sizes
     if let Ok(meta1) = std::fs::metadata("/tmp/iterm_window.png") {
         if let Ok(meta2) = std::fs::metadata("/tmp/fullscreen.png") {