mtmd: add chunks and fix preproc for qwen3a (#23073)

* mtmd: add chunks and fix preproc for qwen3a

* add attn_mask

* limit mtmd_chunk size (avoid blow up memory)

* correct audio tokens

* re-order the set_input case

* remove attn_mask

tools/mtmd/clip-graph.h

@@ -11,6 +11,10 @@
 
 #define DEFAULT_INTERPOLATION_MODE (GGML_SCALE_MODE_BILINEAR | GGML_SCALE_FLAG_ANTIALIAS)
 
+struct build_vit_opts {
+    ggml_tensor * attn_mask = nullptr;
+};
+
 struct clip_graph {
     const clip_model & model;
     const clip_hparams & hparams;
@@ -63,7 +67,8 @@ struct clip_graph {
                 norm_type norm_t,
                 ffn_op_type ffn_t,
                 ggml_tensor * learned_pos_embd,
-                std::function<ggml_tensor *(ggml_tensor *, const clip_layer &)> add_pos);
+                std::function<ggml_tensor *(ggml_tensor *, const clip_layer &)> add_pos,
+                const build_vit_opts & opts = {});
 
     // build the input after conv2d (inp_raw --> patches)
     // returns tensor with shape [n_embd, n_patches]