Fix lint errors: handle errors, use fmt.Fprintf, apply De Morgan's law, use switch statements

Amp-Thread-ID: https://ampcode.com/threads/T-afcf56b0-a8bc-4310-bb59-1b63e1d70c89
Co-authored-by: Amp <amp@ampcode.com>

cmd/bd/daemon.go

@@ -1038,7 +1038,7 @@ func runDaemonLoop(interval time.Duration, autoCommit, autoPush bool, logPath, p
 			}
 			return
 		case <-ctx.Done():
-			log("Context cancelled, shutting down")
+			log("Context canceled, shutting down")
 			if err := server.Stop(); err != nil {
 				log("Error stopping RPC server: %v", err)
 			}