Fix repeated comment-run indentation

Co-authored-by: bergmeister <9250262+bergmeister@users.noreply.github.com>

Author: Copilot

Rules/UseConsistentIndentation.cs

@@ -466,14 +466,18 @@ private static int GetCommentRunIndentationOffset(
             while (nextCommentIndex < tokens.Length &&
                 tokens[nextCommentIndex].Kind == TokenKind.Comment)
             {
+                int firstCommentInGroup = nextCommentIndex;
                 int currentCommentEndLine = tokens[nextCommentIndex].Extent.EndLineNumber;
                 while (nextCommentIndex < tokens.Length &&
                     tokens[nextCommentIndex].Kind == TokenKind.Comment &&
                     tokens[nextCommentIndex].Extent.StartLineNumber <= currentCommentEndLine)
                 {
-                    leastIndentedColumn = Math.Min(
-                        leastIndentedColumn,
-                        tokens[nextCommentIndex].Extent.StartColumnNumber);
+                    if (nextCommentIndex == firstCommentInGroup)
+                    {
+                        leastIndentedColumn = Math.Min(
+                            leastIndentedColumn,
+                            tokens[nextCommentIndex].Extent.StartColumnNumber);
+                    }
                     currentCommentEndLine = Math.Max(
                         currentCommentEndLine,
                         tokens[nextCommentIndex].Extent.EndLineNumber);

Tests/Rules/UseConsistentIndentation.tests.ps1

@@ -343,6 +343,22 @@ if ($a) {
                 Should -Be $scriptDefinition
         }
 
+        It 'Should not increase indentation across a multiline block comment when repeatedly formatted' {
+            $scriptDefinition = @'
+if ($a) {
+    <# first
+#> <# second #>
+        # nested
+}
+'@
+            $settings.Rules.PSUseConsistentIndentation.PipelineIndentation = 'NoIndentation'
+
+            $formatted = Invoke-Formatter -ScriptDefinition $scriptDefinition -Settings $settings
+            $formatted | Should -Be $scriptDefinition
+            Invoke-Formatter -ScriptDefinition $formatted -Settings $settings |
+                Should -Be $scriptDefinition
+        }
+
         It 'Should preserve indentation with many adjacent block comments' {
             $comments = (1..16 | ForEach-Object { "<# comment $_ #>" }) -join ' '
             $scriptDefinition = @(