Fix replica-without-db logger (#512)

Makefile

@@ -20,7 +20,8 @@ ifndef LITESTREAM_VERSION
 	$(error LITESTREAM_VERSION is undefined)
 endif
 	mkdir -p dist
-	go build -v -ldflags "-s -w -X 'main.Version=${LITESTREAM_VERSION}'"  -o dist/litestream ./cmd/litestream
+
+	GOOS=darwin GOARCH=amd64 CC="gcc -target amd64-apple-macos11" CGO_ENABLED=1 go build -v -ldflags "-s -w -X 'main.Version=${LITESTREAM_VERSION}'"  -o dist/litestream ./cmd/litestream
 	gon etc/gon.hcl
 	mv dist/litestream.zip dist/litestream-${LITESTREAM_VERSION}-darwin-amd64.zip
 	openssl dgst -sha256 dist/litestream-${LITESTREAM_VERSION}-darwin-amd64.zip

replica.go

@@ -99,7 +99,11 @@ func (r *Replica) Name() string {
 
 // Logger returns the DB sub-logger for this replica.
 func (r *Replica) Logger() *slog.Logger {
-	return r.db.Logger.With("replica", r.Name())
+	logger := slog.Default()
+	if r.db != nil {
+		logger = r.db.Logger
+	}
+	return logger.With("replica", r.Name())
 }
 
 // DB returns a reference to the database the replica is attached to, if any.