Play confirmation sound when copying server command (#181)

"Copy server command to clipboard" silently copies with no feedback,
so there's no way to tell the click registered. Play the existing
system Pop sound cue on copy, matching the confirmation pattern
already used elsewhere in the app.


Claude-Session: https://claude.ai/code/session_01QLDiNzrDds62dnD9NoCEJV

Co-authored-by: Claude Sonnet 5 <noreply@anthropic.com>

Author: Arsey

App/Views/ContentView.swift

@@ -91,6 +91,8 @@ struct ContentView: View {
                     let pasteboard = NSPasteboard.general
                     pasteboard.clearContents()
                     pasteboard.setString(command, forType: .string)
+
+                    _ = NSSound.play(.pop)
                 }
             }
             .padding(.top, 8)