fix(mtmd): handle Gemma 4 audio projector embedding size (#24091)

* mtmd: handle Gemma 4 audio projector embedding size

* rm projection_dim from clip_n_mmproj_embd

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Co-authored-by: Xuan Son Nguyen <son@huggingface.co>

Author: abetlen

tools/mtmd/clip.cpp

@@ -4347,6 +4347,8 @@ int clip_n_mmproj_embd(const struct clip_ctx * ctx) {
             return ctx->model.mm_input_proj_w->ne[0];
         case PROJECTOR_TYPE_GEMMA4V:
         case PROJECTOR_TYPE_GEMMA4UV:
+        case PROJECTOR_TYPE_GEMMA4A:
+        case PROJECTOR_TYPE_GEMMA4UA:
             return ctx->model.mm_input_proj_w->ne[1];
         case PROJECTOR_TYPE_IDEFICS3:
             return ctx->model.mm_fc_w->ne[1];
@@ -4381,8 +4383,6 @@ int clip_n_mmproj_embd(const struct clip_ctx * ctx) {
             return ctx->model.mm_fc_w->ne[1];
         case PROJECTOR_TYPE_LFM2A:
             return ctx->model.position_embeddings->ne[0];
-        case PROJECTOR_TYPE_GEMMA4UA:
-            return ctx->model.hparams.projection_dim;
         case PROJECTOR_TYPE_GRANITE_SPEECH:
             return ctx->model.qf_proj_linear_w->ne[1];
         case PROJECTOR_TYPE_GLM4V: