chore: add contributions script

scripts/contributions_digester.dart

@@ -0,0 +1,31 @@
+import 'dart:io';
+
+/// Used to make the changes in the Github Releases shorter.
+/// Aggregates documentation and i18n PRs to "i18n: @user1, @user2".
+/// Keeps other contributions (PRs) as is.
+void main() {
+  final contributions = File('contributions.txt').readAsLinesSync();
+  final newContributions = <String>[];
+  final documentations = <String>{}; // list of "@user"
+  final translators = <String>{}; // list of "@user"
+  for (String pr in contributions) {
+    pr = pr.toLowerCase();
+    if (pr.contains('@dependabot')) {
+      continue;
+    }
+
+    if (pr.contains('i18n') || pr.contains('translation') || pr.contains('translator') || pr.contains('language')) {
+      translators.add('@' + pr.split(' @').last);
+    } else if (pr.contains('readme') || pr.contains('contributing')) {
+      documentations.add('@' + pr.split(' @').last);
+    } else {
+      newContributions.add(pr);
+    }
+  }
+
+  final content = newContributions.join('\n') + '\n' + '* docs: ${documentations.join(', ')}' + '\n' + '* i18n: ${translators.join(', ')}';
+  print('Content: $content');
+
+  File('contributions_digested.txt').writeAsStringSync(content);
+  print('Finish!');
+}