feat: recording capsule (#38)

meetingnotes/MeetingnotesApp.swift

@@ -43,7 +43,19 @@ struct MeetingnotesApp: App {
             CommandGroup(after: .appInfo) {
                 CheckForUpdatesView(updater: updaterController.updater)
             }
+            // Hidden command group that handles audio level window notifications
+            CommandGroup(after: .windowArrangement) {
+                ShowAudioLevelsCommand()
+            }
         }
+        
+        // Floating Audio Level Window
+        Window("", id: "audio-levels") {
+            AudioLevelWindowView()
+        }
+        .windowStyle(.plain)
+        .windowResizability(.contentSize)
+        .defaultPosition(.trailing)
     }
 }
 
@@ -57,3 +69,18 @@ struct CheckForUpdatesView: View {
         .keyboardShortcut("u", modifiers: .command)
     }
 }
+
+struct ShowAudioLevelsCommand: View {
+    @Environment(\.openWindow) private var openWindow
+    
+    var body: some View {
+        // Empty view - we only need this for the notification observer
+        EmptyView()
+            .onReceive(NotificationCenter.default.publisher(for: .openAudioLevelWindow)) { _ in
+                openWindow(id: "audio-levels")
+                DispatchQueue.main.asyncAfter(deadline: .now() + 0.1) {
+                    AudioLevelWindowManager.shared.showWindow()
+                }
+            }
+    }
+}