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>

core/tiny_debug_ring.h

@@ -0,0 +1,41 @@
+#ifndef TINY_DEBUG_RING_H
+#define TINY_DEBUG_RING_H
+
+#include <stdint.h>
+#include <stddef.h>
+
+// Tiny Debug Ring Trace (Phase 8 tooling)
+// Environment: HAKMEM_TINY_TRACE_RING=1 to enable
+// Records recent alloc/free events and dumps them on SIGSEGV.
+
+enum {
+    TINY_RING_EVENT_ALLOC_ENTER = 1,
+    TINY_RING_EVENT_ALLOC_SUCCESS,
+    TINY_RING_EVENT_ALLOC_NULL,
+    TINY_RING_EVENT_ALLOC_REFILL_START,
+    TINY_RING_EVENT_ALLOC_REFILL_NULL,
+    TINY_RING_EVENT_ALLOC_BIND,
+    TINY_RING_EVENT_FREE_ENTER,
+    TINY_RING_EVENT_FREE_FAST,
+    TINY_RING_EVENT_FREE_REMOTE,
+    TINY_RING_EVENT_FREE_LOCAL,
+    TINY_RING_EVENT_FREE_RETURN_MAG,
+    TINY_RING_EVENT_SUPERSLAB_ADOPT,
+    TINY_RING_EVENT_SUPERSLAB_ALLOC,
+    TINY_RING_EVENT_SUPERSLAB_PUBLISH,
+    TINY_RING_EVENT_SUPERSLAB_ADOPT_FAIL,
+    TINY_RING_EVENT_REMOTE_PUSH,
+    TINY_RING_EVENT_REMOTE_INVALID,
+    TINY_RING_EVENT_REMOTE_DRAIN,
+    TINY_RING_EVENT_OWNER_ACQUIRE,
+    TINY_RING_EVENT_OWNER_RELEASE,
+    TINY_RING_EVENT_FRONT_BYPASS,
+    TINY_RING_EVENT_MAILBOX_PUBLISH,
+    TINY_RING_EVENT_MAILBOX_FETCH,
+    TINY_RING_EVENT_MAILBOX_FETCH_NULL
+};
+
+void tiny_debug_ring_init(void);
+void tiny_debug_ring_record(uint16_t event, uint16_t class_idx, void* ptr, uintptr_t aux);
+
+#endif // TINY_DEBUG_RING_H