Merge pull request #108 from jakehemmerle/fix/daemon-orphan-race-condition

fix(daemon): prevent orphan daemons via file locking

internal/cmd/daemon.go

@@ -117,7 +117,7 @@ func runDaemonStart(cmd *cobra.Command, args []string) error {
 		return fmt.Errorf("starting daemon: %w", err)
 	}
 
-	// Wait a moment for the daemon to initialize
+	// Wait a moment for the daemon to initialize and acquire the lock
 	time.Sleep(200 * time.Millisecond)
 
 	// Verify it started
@@ -129,6 +129,15 @@ func runDaemonStart(cmd *cobra.Command, args []string) error {
 		return fmt.Errorf("daemon failed to start (check logs with 'gt daemon logs')")
 	}
 
+	// Check if our spawned process is the one that won the race.
+	// If another concurrent start won, our process would have exited after
+	// failing to acquire the lock, and the PID file would have a different PID.
+	if pid != daemonCmd.Process.Pid {
+		// Another daemon won the race - that's fine, report it
+		fmt.Printf("%s Daemon already running (PID %d)\n", style.Bold.Render("●"), pid)
+		return nil
+	}
+
 	fmt.Printf("%s Daemon started (PID %d)\n", style.Bold.Render("✓"), pid)
 	return nil
 }