Loading Incomplete Cache After Benchmark Preprocessing Failure

[zhizhou57]

If a benchmark task fails during preprocessing, flagevalmm saves incomplete cache data. When rerunning the task, it reads from this corrupted cache, causing repeated failures.

Steps to Reproduce:
1. Run a benchmark task that fails during preprocessing. (Such as using ctrl+c)
2. Re-run the same task.
3. It fails due to reading incomplete cached data.

Expected Behavior:
• Detect and remove corrupted cache files.
• Provide an option to force re-preprocessing.