DEBUG: try plain Python int kv_coord (like CUTLASS ref)

tests/unit/test_fmha_v3_stage_c_full.py

@@ -209,7 +209,7 @@ class FmhaV3StageC:
             cute.copy(tma_q, tAgQ[(None, Int32(0))], tAsQ[(None, qh.index)], tma_bar_ptr=qh.barrier)
             qp.tail()
             kvp.reset(); pk = kvp.try_acquire()
-            kv_coord = Int32(1)  # DEBUG: hardcoded to 1 to test if TMA actually uses it
+            kv_coord = 0  # Plain Python int, like CUTLASS reference
             for kt in cutlass.range(n_kv_tiles, unroll=1):
                 kvh = kvp.acquire_and_advance(pk)
                 cute.copy(tma_k, tBgK[(None, kv_coord)], tBsK[(None, kvh.index)], tma_bar_ptr=kvh.barrier)