feat(mem-alloc): add realloc rejection for aligned allocs

gc_realloc_vo now detects and rejects aligned allocations
per POSIX behavior.

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

Author: lum1n0us

core/shared/mem-alloc/ems/ems_alloc.c

@@ -778,6 +778,16 @@ gc_realloc_vo_internal(void *vheap, void *ptr, gc_size_t size, const char *file,
     }
 #endif
 
+    /* Check if this is an aligned allocation - not supported */
+    if (obj_old) {
+        uint32_t *magic_ptr = (uint32_t *)((char *)obj_old - 4);
+        if ((*magic_ptr & ALIGNED_ALLOC_MAGIC_MASK) == ALIGNED_ALLOC_MAGIC_VALUE) {
+            LOG_ERROR("[GC_ERROR]gc_realloc_vo does not support aligned "
+                      "allocations\n");
+            return NULL;
+        }
+    }
+
     if (obj_old) {
         hmu_old = obj_to_hmu(obj_old);
         tot_size_old = hmu_get_size(hmu_old);