fix: set inputs and force CPU idxs before Phase 2 capture/alloc (#huanglawsded)

Author: Alex7MV

src/llama-context.cpp

@@ -1884,6 +1884,12 @@ llm_graph_result * llama_context::process_ubatch(const llama_ubatch & ubatch, ll
                         phase2_gf = model.build_graph(gparams, nullptr, nullptr, &moe_weight_cache);
                         if (!phase2_gf) { ret = GGML_STATUS_FAILED; return nullptr; }
 
+                        // Inputs must be written and CPU-assigned before capture.
+                        // alloc_graph needs the final shapes and host-buffer inputs,
+                        // and the persistent graph will share these tensor objects.
+                        force_idxs_to_cpu_p2();
+                        res->set_inputs(&ubatch);
+
                         // Persist the Phase 2 graph structure across res->reset().
                         // Tensor objects remain shared with the freshly built graph, so
                         // framework-owned backend metadata is preserved exactly.