style: remove em dashes from fixture files

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: homeofe

src/fixtures/bugfix.diff

@@ -44,7 +44,7 @@ index a571005..1604b46 100644
    stepName: string;
    errorLines: string[];
 @@ -84,15 +104,28 @@ function extractContext(
-   // Focus on the last error — most likely the root cause
+   // Focus on the last error - most likely the root cause
    const lastErrorIdx = errorIndices[errorIndices.length - 1];
 
 -  // Scan backwards from last error to find nearest ##[group]