Optimize stroke cache and benchmark configurations

- Updated stroke cache to use parallel processing for pixel checks.
- Modified benchmark commands in notlar.txt to ensure consistent output and baseline comparisons.
- Created a plan for merging criterion directories and optimizing benchmark performance, including pre-allocation of buffers and various optimization strategies.
- Removed redundant output directory settings in benchmark files and ensured all benchmarks write to a single criterion directory.
- Updated documentation to reflect changes in benchmark paths and configurations.

.gitignore

@@ -51,6 +51,10 @@ Thumbs.db
 _images
 _tmp
 .history
+
+# Criterion benchmark output (generated, gold_standard baseline kept manually)
+/criterion/
+
 # Custom dev environment
 /.rustup/
 /logs/last_semantic_audit.txt