Fix dart analysis

Author: mugikhan

analysis_options.yaml

@@ -22,8 +22,11 @@ linter:
   # `// ignore_for_file: name_of_lint` syntax on the line or in the file
   # producing the lint.
   rules:
-    # avoid_print: false  # Uncomment to disable the `avoid_print` rule
+    avoid_print: false # Uncomment to disable the `avoid_print` rule
     # prefer_single_quotes: true  # Uncomment to enable the `prefer_single_quotes` rule
-
 # Additional information about this file can be found at
 # https://dart.dev/guides/language/analysis-options
+
+analyzer:
+  exclude:
+    - lib/firebase.dart # Exclude this as it imports a file that is not checked in

lib/powersync.dart

@@ -29,7 +29,7 @@ final List<RegExp> fatalResponseCodes = [
 /// Use Custom Node.js backend for authentication and data upload.
 class BackendConnector extends PowerSyncBackendConnector {
   PowerSyncDatabase db;
-
+  //ignore: unused_field
   Future<void>? _refreshFuture;
 
   BackendConnector(this.db);