mtmd: deepseek-ocr v1 multi-tile (#24717)

* mtmd: deepseek-ocr v1 multi-tile dynamic resolution + unified image-preprocessors for both versions (ds-ocr v1 and v2)

* remove hacky API

* fuse row into a long image

* almost working

* adapt to new preprocessor api

* rm debugging printf

* improve

* mtmd: dsocr-tiles fixes (#25481)

* ds-ocr img-preproc fuse_row tile-drop fix for multi rows and columns images

* mtmd drop the duplicate redundant img_end

* deepseekocr graph simplify CLS broadcast cleanup

* test-deepseek-ocr: relax v1 single-view tolerance; drop trailing prompt space; make DRY opt-in and n_predict model-specific (#25486)

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Co-authored-by: Saba Fallah <10401143+sfallah@users.noreply.github.com>
Co-authored-by: Saba Fallah <sabafallah@gmail.com>

tools/mtmd/models/models.h

@@ -127,6 +127,7 @@ struct clip_graph_deepseekocr : clip_graph {
     clip_graph_deepseekocr(clip_ctx * ctx, const clip_image_f32 & img) : clip_graph(ctx, img) {}
     ggml_cgraph * build() override;
     ggml_tensor * build_sam(ggml_tensor * inp); // build the SAM model
+    // bool support_batch() const override { return true; } // TODO: support batch for DeepSeek-OCR v1
 };
 
 struct clip_graph_deepseekocr2 : clip_graph_deepseekocr {