* kv-cache : use ggml_backend_tensor_copy to refill the DSV4 K mirrors
* llama : move the Engram pad id to llama_hparams and the token map to llama_model
The saver no longer needs the deepseek41 model class.
* deepseek41 : drop the F32 src1 request on the HC mixes matmul
* ggml : add softplus TODOs in the backends that still use log(1 + exp(x))
* convert : make the DSV4/DSV4.1 modify_tensors generators, drop the redundant vision filter
* deepseek41 : clean up comments
* deepseek41 : drop the F32 src1 requests on the router and indexer matmuls
* convert : use format_tensor_name directly in DeepseekV4Model
* s/comp_kv_src/comp_il_src/g
* cont : fix TODOs for log1p
---------
Co-authored-by: Georgi Gerganov <ggerganov@gmail.com>