refactor: streamline base reference handling in version function

Author: flxapps

lib/version/version.dart

@@ -77,12 +77,6 @@ Future<VersionResult> version({
     cache: cache,
   );
 
-  final baseRefForPubspec = baseRef ??
-      (packageName != null
-          ? await GitUtils.getPreviousRefForPackage(gitRoot.path, packageName, tagPrefix: 'v') ??
-              (throw Exception('No previous version found for package $packageName'))
-          : await GitUtils.getPreviousRef(gitRoot.path, tagPrefix: tagPrefix));
-
   final pubspecPath =
       packageName != null ? join(relative(dartRoot.path, from: gitRoot.path), 'pubspec.yaml') : 'pubspec.yaml';
 
@@ -91,7 +85,7 @@ Future<VersionResult> version({
   applyMagnitudeOverrides(changes, config);
 
   final basePubSpec = await GitUtils.gitShow(
-    baseRefForPubspec,
+    effectiveBaseRef,
     gitRoot.path,
     pubspecPath,
   );
@@ -145,7 +139,7 @@ Future<VersionResult> version({
   }
 
   if (badge) {
-    final badgeContent = await generateVersionBadge(nextVersion);
+    badgeContent = await generateVersionBadge(nextVersion);
     await File(join(dartRoot.path, 'version_badge.svg')).writeAsString(badgeContent);
     logger.info('Generated version badge for version $nextVersion');
   }