feat: dev server improvements - recursive watching, auto-open browser

- Recursive file watching: catches imported file changes from registry/
- Auto-detect project root: walks up to find registry/ or examples/ dir
- Auto-open browser on startup (xdg-open/open/cmd)
- Verified HMR live reload: 0ms recompile on file save

compiler/ds-cli/src/main.rs

@@ -347,10 +347,28 @@ h2 {{ color: #f87171; margin-bottom: 16px; }}
             }
         }).expect("Failed to create file watcher");
 
-        watcher.watch(&watch_dir, RecursiveMode::NonRecursive)
+        watcher.watch(&watch_dir, RecursiveMode::Recursive)
             .expect("Failed to watch directory");
 
-        println!("👁  Watching {} for changes", watch_dir.display());
+        // Also watch project root (for registry/components etc.)
+        // Walk up from watch_dir to find a directory containing examples/ or registry/
+        let mut project_root = watch_dir.clone();
+        for _ in 0..5 {
+            if project_root.join("registry").is_dir() || project_root.join("examples").is_dir() {
+                if project_root != watch_dir {
+                    let _ = watcher.watch(&project_root, RecursiveMode::Recursive);
+                    println!("👁  Also watching {} (project root)", project_root.display());
+                }
+                break;
+            }
+            if let Some(parent) = project_root.parent() {
+                project_root = parent.to_path_buf();
+            } else {
+                break;
+            }
+        }
+
+        println!("👁  Watching {} for changes (recursive)", watch_dir.display());
         println!();
 
         // Debounce: coalesce rapid events
@@ -418,6 +436,15 @@ h2 {{ color: #f87171; margin-bottom: 16px; }}
     println!("   Press Ctrl+C to stop");
     println!();
 
+    // Auto-open browser
+    let url = format!("http://localhost:{port}");
+    #[cfg(target_os = "linux")]
+    { let _ = std::process::Command::new("xdg-open").arg(&url).spawn(); }
+    #[cfg(target_os = "macos")]
+    { let _ = std::process::Command::new("open").arg(&url).spawn(); }
+    #[cfg(target_os = "windows")]
+    { let _ = std::process::Command::new("cmd").args(["/C", "start", &url]).spawn(); }
+
     for request in server.incoming_requests() {
         let url = request.url().to_string();