Debug Counters Implementation - Clean History

Major Features:
- Debug counter infrastructure for Refill Stage tracking
- Free Pipeline counters (ss_local, ss_remote, tls_sll)
- Diagnostic counters for early return analysis
- Unified larson.sh benchmark runner with profiles
- Phase 6-3 regression analysis documentation

Bug Fixes:
- Fix SuperSlab disabled by default (HAKMEM_TINY_USE_SUPERSLAB)
- Fix profile variable naming consistency
- Add .gitignore patterns for large files

Performance:
- Phase 6-3: 4.79 M ops/s (has OOM risk)
- With SuperSlab: 3.13 M ops/s (+19% improvement)

This is a clean repository without large log files.

🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude <noreply@anthropic.com>

include/hakmem_libc.h

@@ -0,0 +1,12 @@
+// HAKMEM libc wrapper declarations
+#ifndef HAKMEM_LIBC_H
+#define HAKMEM_LIBC_H
+
+#include <stddef.h>
+
+void* hkm_libc_malloc(size_t size);
+void* hkm_libc_calloc(size_t count, size_t size);
+void* hkm_libc_realloc(void* ptr, size_t size);
+void hkm_libc_free(void* ptr);
+
+#endif