Fix: Move g_hakmem_lock_depth++ to function start (27% → 70% success)

**Problem**: After previous fixes, 4T Larson success rate dropped 27% (4/15)

**Root Cause**:
In `log_superslab_oom_once()`, `g_hakmem_lock_depth++` was placed AFTER
`getrlimit()` call. However, the function was already called from within
malloc wrapper context where `g_hakmem_lock_depth = 1`.

When `getrlimit()` or other LIBC functions call `malloc()` internally,
they enter the wrapper with lock_depth=1, but the increment to 2 hasn't
happened yet, so getenv() in wrapper can trigger recursion.

**Fix**:
Move `g_hakmem_lock_depth++` to the VERY FIRST line after early return check.
This ensures ALL subsequent LIBC calls (getrlimit, fopen, fclose, fprintf)
bypass HAKMEM wrapper.

**Result**: 4T Larson success rate improved 27% → 70% (14/20 runs) ✅
+43% improvement, but 30% crash rate remains (continuing investigation)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

core/hakmem_tiny_superslab.c

@@ -117,6 +117,12 @@ static void log_superslab_oom_once(size_t ss_size, size_t alloc_size, int err) {
     if (logged) return;
     logged = 1;
 
+    // CRITICAL FIX: Increment lock depth FIRST before any LIBC calls
+    // fopen/fclose/getrlimit/fprintf all may call malloc internally
+    // Must bypass HAKMEM wrapper to avoid header mismatch crash
+    extern __thread int g_hakmem_lock_depth;
+    g_hakmem_lock_depth++;  // Force wrapper to use __libc_malloc
+
     struct rlimit rl = {0};
     if (getrlimit(RLIMIT_AS, &rl) != 0) {
         rl.rlim_cur = RLIM_INFINITY;
@@ -125,10 +131,6 @@ static void log_superslab_oom_once(size_t ss_size, size_t alloc_size, int err) {
 
     unsigned long vm_size_kb = 0;
     unsigned long vm_rss_kb = 0;
-    // CRITICAL FIX: fopen/fclose use GLIBC malloc/free internally
-    // Must bypass HAKMEM wrapper to avoid header mismatch crash
-    extern __thread int g_hakmem_lock_depth;
-    g_hakmem_lock_depth++;  // Force wrapper to use __libc_malloc
     FILE* status = fopen("/proc/self/status", "r");
     if (status) {
         char line[256];