Two-Speed HOT PATH: Guard hak_super_lookup calls with HAKMEM_BUILD_RELEASE

Phase E2 introduced registry lookup to the hot path, causing 84-88% regression
(70M → 9M ops/sec). This commit restores performance by guarding expensive
hak_super_lookup calls (50-100 cycles each) with conditional compilation.

Key changes:
- tls_sll_box.h push: Full validation in Debug, ss_fast_lookup (O(1)) in Release
- tls_sll_box.h pop: Registry validation in Debug, trust list structure in Release
- tiny_free_fast_v2.inc.h: Header/meta cross-check Debug-only
- malloc_tiny_fast.h: SuperSlab registration check Debug-only

Performance improvement:
- Release build: 2.9M → 87-88M ops/sec (30x improvement)
- Restored to historical UNIFIED-HEADER peak (70-80M range)

Release builds trust:
- Header magic (0xA0) as sufficient allocation origin validation
- TLS SLL linked list structure integrity
- Header-based class_idx classification

Debug builds maintain full validation with expensive registry lookups.

🤖 Generated with Claude Code

Co-Authored-By: Claude <noreply@anthropic.com>

core/front/malloc_tiny_fast.h

@@ -155,11 +155,15 @@ static inline int free_tiny_fast(void* ptr) {
     // 4. BASE を計算して Unified Cache に push
     void* base = (void*)((char*)ptr - 1);
 
+    // TWO-SPEED: SuperSlab registration check is DEBUG-ONLY to keep HOT PATH fast.
+    // In Release builds, we trust header magic (0xA0) as sufficient validation.
+#if !HAKMEM_BUILD_RELEASE
     // 5. Superslab 登録確認（誤分類防止）
     SuperSlab* ss_guard = hak_super_lookup(ptr);
     if (__builtin_expect(!(ss_guard && ss_guard->magic == SUPERSLAB_MAGIC), 0)) {
         return 0;  // hakmem 管理外 → 通常 free 経路へ
     }
+#endif  // !HAKMEM_BUILD_RELEASE
 
     // Cross-thread free detection (Larson MT crash fix, ENV gated)
     {